PROFESSOR JAYASHANKAR TELANGANA AGRICULTURAL UNIVERSITY

DEPARTMENT OF HORTICULTURE

STUDY MATERIAL

COURSE NO. HORT-181

COURSE TITLE . FUNDAMENTALS OF HORTICULTURE
(As per VI Dean Syllabus)

Fundamentals of Horticulture 3(2+1)

Dr.I.V.Srinivasa Reddy,
Professor,
Department of Horticulture,
Agriculture college, Aswaraopet -507301
9441168156
drivsreddy@gmail.com
&
Dr.A.Venkatram,
Assistant Professor,
Department of Horticulture,
BJR Agriculture college, Sircilla

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 PROFESSOR JAYASHANKAR TELANGANA AGRICULTURAL UNIVERSITY
DEPARTMENT OF HORTICULTURE
DETAILED LECTURE OUTLINE

Course No. : HORT 181

Course title : Fundamentals of Horticulture
Credits : 3(2+ 1)
Semester : First semester
Academic level : B.Sc. (Hons.) Agriculture
At entry : B. Sc.(Ag.) First year

Objectives
1. To provide knowledge on different branches of horticulture viz. Pomology, Olericulture,
Floriculture and landscaping, spices and medicinal plants
2. To provide knowledge on orchard management, propagation methods, cultural operations
and nutrient management of horticultural crops
3. To provide knowledge on different physiological aspects of horticultural crops
S.No Reference Page No.
Title of the Lecture
book (s)
1. Definition – Horticulture Vs Agriculture - Importance of Horticulture 1,2 & 3 5-6
in terms of economics, employment generation, environment
protection and human resource development
2. Nutrition value of Horticulture crops 1,2 & 3 6-7
3. Divisions of Horticulture-their definition with crop examples and 1,2 & 3 7-8
their importance
4. Horticulture and Botanical classification – classification based on 1,2 & 3 8-11
nature of growth habit, life span, climatic requirement, growing
season, continuation of growth, bearing behavior, water requirement,
light requirement, photoperiodic requirement, fruits classification
based on types, edible part, ripening behavior.
5. Climate and Soil requirements for Horticultural crops-Temperature, 1,2 & 3 11-16
Humidity, Wind, Rainfall and Solar Radiation -
cultivation of horticultural crops in different agro-ecological zones
in India.
6. Planning of Orchard – definition of orchard, orcharding, garden, 1,2 & 3 16-20
plantation, estate, types of orchards – advantages and disadvantages
with examples - Points to be considered for Selection of site for
establishment of orchard.
7. Principles of orchard establishment 1,2 & 3
8. Steps in establishment of orchard-Clearing the Land, Levelling, 1,2 & 3 20-24
Fencing, Wind breaks, Selection of Plants from the nursery, Season
of Planting, Planting and Healing inn.
9. Planting systems- Lay out- Different systems of Planting -Square, 1,2 & 3 24-30
Rectangular, Quincunx, Hexagonal, and contour Planting with their
merits and demerits
10. High density planting / high density orcharding – categories of HDP, 1,2 & 3 31-33
Advantage, Components of HDP, Methods of HDP- tree size control,
use of dwarfing rootstock, training pruning, use of growth retardents,
impact of HDP in major fruits.
11. Propagation –Definition- Methods of Propagation-Sexual - 1,2 & 3 34-35
Advantages and disadvantages

12. Asexual - Advantages and disadvantages 1,2 & 3 35-36

13. Seed germination- Dormancy-Reasons for Seed dormancy, Methods 1,2 & 3 37-38
to overcome Seed Dormancy
14. Definition of division and Separation –Methods of division-Bulbs 1,2 & 3 39-43
and Corms and Separation Stem tuber, Tuberous root, Rhizome,
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 Suckers, (shoot and root suckers) runner and Off sets- Example for
each type.
15. Plant Propagation Structures- Green house, Lath house, Hot bed, 1,2 & 3 44-46
Cold Frame, and other propagating frames.
16. Propagation by Cuttings-Definition of Cutting-Different methods of 1,2 & 3 46-50
Cuttings-Stem cuttings- Hard wood cuttings, Semi hard wood, Soft
wood and Herbaceous stem cuttings –example for each type. Leaf
cuttings.
17. Plant propagation by layering-Definition of Layering and Layer- 1,2 & 3 51-54
Types of Layering- Tip layering, Simple layering, Trench layering,
mound or Stool layering, Compound or Serpentine layering-Air
layering- Examples for each layering.
18. Plant Propagation by Grafting-Definition of Grafting-Methods of 1,2 & 3 54-56
Grafting- Attached scion method of Grafting, Simple or Approach
grafting,
19. Detached methods of Grafting-Veneer grafting, Side Grafting, 1,2 & 3 56-59
Epicotyl grafting, Soft wood grafting, Double working, Top working.
20. Stock-scion relationship – effect of rootstock on scion, effect of scion 1,2 & 3 60-61
on rootstock; Graft incompatibility - types of graft incompatibilty

21. Plant propagation by Budding-Definition of Budding-Methods of 1,2 & 3 62-64

Budding-T- budding and Inverted T budding, Patch budding, Ring
budding
22. Training- Definition –Objectives of Training fruit trees-Methods of 1,2 & 3 64-69
Training- Central leader , Open centre and Modified Leader system
with merits and demerits.
23. Pruning-Definition –Objectives of Pruning- Response of plant to 1,2 & 3 69-72
pruning-Methods of Pruning-Thinning out, Trimming, Heading
Back, Pollarding, Pinching, Disbudding, Deblossoming, -Season of
Pruning- Pruning and Manuring, Care of Pruned wounds.
24. Unfruitfulness in fruit trees, Causes-Environmental causes, 1,2 & 3 72-74
Nutritional causes, Inherent causes, Biological causes, and cultural
causes and their remedies.
25. Pollination, Pollinizers, and Pollinators – problems and role in 1,2 & 3 75-77
horticulture production
26. Juvenility-Definition, Flower bud differentiation- Influence of 1,2 & 3 77-80
various factors on flower bud initiation. Environmental – Chemical
– Nutritional - managemental. Types of Buds, Fertilization-
Definition and Types of Fertilization and Apomixis
27. Parthenocarpy-Definition and Types of Parthenocarpy. 1,2 & 3 81-82
28. Maturity, harvesting, grading, packaging and storage of important 1,2 & 3 83-86
fruits , vegetables and flowers
29. Flower and Fruit drop – stages, causes – remedial measures 1,2 & 3 87-88
30. Role of bio regulators in Propagation- Control of Flowering, Fruit 1,2 & 3 89-91
set, Fruit drop, Parthenocarpy, Fruit ripening, Fruit size, quality, and
Sex expression.
31. Water management –Irrigation - Methods of Irrigation- Surface 1,2 & 3 92-95
Check basin, Furrow, Ring Basin, Basin, Flood, Pitcher, Drip and
Sprinkler irrigation system and their merits and demerits.
32. Fertilizer application in Fruit Crops-Types of Fertilizers-Time of 1,2 & 3 96-98
Fertilizer application, Methods of Fertilizers application-Broad
casting-advantages and Disadvantages, Band placement, Ring
Placement, Foliar application, Starter solutions, Fertigation.

HORT 181
S.No Practical class outlines
1. Visit to College Orchard
2. Identification of Horticultural crops
3. Study of Horticultural tools and implements
4. Lay out and Planting of Orchard

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5. Preparation of Potting mixture and Potting
6. Preparation of Seed bed/ Nursery bed
7. Vegetative Propagation by corms, Bulbs, Rhizomes, etc.,
8. Vegetative Propagation by Cuttings
9. Vegetative Propagation by Layerings
10. Vegetative Propagation by Grafting
11. Vegetative Propagation by Budding
12 Preparation of Growth regulators-powder, Solution, and Lanolin paste,
13 Study of Pruning and Training in Fruit trees
14 Methods of Fertilizer application in fruit crops
15 Layout of different irrigation systems in fruit crops
16 Study of Maturity, harvesting, grading, packaging and storage of important fruits ,
vegetables and flowers

References

Sl.No. Book title & Author Publisher

1. Basics of Horticulture, Jitendra Singh Kalyani Publishers, Ludhiana

2. Introduction to Horticulture-Kumar, Rajyalakshmi Publications, Nagorcoil,

N.1990. Tamilnadu
3. Hand Book of Horticulture ICAR, New-Delhi
4. Propagation of Horticultural Crops: Kalyani Publishers, Ludhiana
Principles & Practices – RR Sharma
2018

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Lecture 1: Definition – Horticulture Vs Agriculture - Importance of Horticulture in terms of economics,
employment generation, environment protection and human resource development

The term Horticulture is derived from two Latin words i.e. Hortus meaning garden or enclosure and Cultra
meaning cultivation. So, horticulture literally means garden culture or culture of garden crops.
The term Agriculture refers broadly to the technology of raising plants and animals. On the other hand
Horticulture which is a part of agriculture is concerned with the raising of so called garden crops.
According to the modern world, horticulture is defined as the crop science which deals with the production,
utilization and improvement of fruits, vegetables, ornamental plants, spices and plantation crops, medicinal
and aromatic plants. Horticultural science can be distinguished from agricultural in one or more of the
following factors

 Horticulture produces are utilized in the fresh state and are highly perishable. In contrast, agricultural
field crops are often utilized in the dried state of are usually high in dry matter content.
 Horticultural crops generally require intensive cultivation warranting a large input, capital, labor and
technology per unit area of land.
 Cultural operations such as propagation, fertilization, training pruning, harvesting and marketing are
skilled operations and are specific to each and every horticulture crops.
 Horticulture crops are rich in sources of vitamins and minerals where as agricultural crops are
generally rich in carbohydrates or protein.
 Aesthetic sense is an exclusive phenomenon for horticulture science.

Importance of Horticulture in terms of economics, employment generation, environment

protection and human resource development:
• The horticulture sector contributes about 30.4 per cent of the agriculture GDP, besides providing
employment for 19 per cent of the labour force.
• As an economic proposition as they give higher returns per unit area in terms of energy,
money,job, etc.
• Employment generation - fruit crops requires 860 man days/annum as against 143 man
days/annum for cereal crops where as the crops like grapes, banana and pineapple needs 1000-
2500 man days per annum.
• As a substitute for family income being the component of home garden/ kitchen garden.
• As a foreign exchange earner, has higher share compare to agriculture crops.
• The demand for horticulture produce is expected to increase owing to increasing urbanization,
income-lead higher standard of living, enhanced awareness of nutrition security and family welfare
programmes.
• Horticultural produces contribute to national wealth. They are the important exportable commodities
in many countries. In India also through export of horticultural produces our country is earning
foreign exchange.
• India exporting flowers to America, Netherlands, Germany, Japan, UK, Onions to Malayasia, UAE,
Singapore, Srilanka and Bangladesh. Vegetables to Srilanka, America, UAE, Spain, Saudi Arabia,
Bangladesh, U.K., Kuawait, Fresh grapes to UK, Netherlands, UAE, Bangladesh, Germany, Fresh
fruits to Bangladesh, UAE, Saudi Arabia, UK and Srilanka. Processed vegetables to Egypt, Srilanka,
UAE, America and Turkey and Mango pulp to Saudi Arabia, UAE, Netherlands, Kuwait and
Germany. Pickles and Chutneys to UK, America, UAE, Spain etc.
• Horticulture is a mother for many axillary industries like canning industries and processing industries
etc. Several agro industries, based on horticultural products are being established there by solving
the unemployment problem to some extent.
Eg.Rubber, Coir (Coconut) and sago (Tapioca) industries.
• Effective utilization of waste land through cultivation of hardy fruits and medicinal plants.
• As a source of variability in produce.
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 • As a source of nutrients, vitamins, minerals, flavour, aroma, alkaloids, oleoresins, fibre, etc.
• As a source of medicine.
• As an input for industry being amenable to processing, especially fruit and vegetable preservation
industry.
• Aesthetic consideration and protection of the environment.
• Religious significance in the country.
• In short and sweet horticulture supplies quality food for health and mind, more calories per unit
area, develops better resources and yields higher returns per unit area.
• It also enhances land value and creates better purchasing power for those who are engaged in
this industry. Therefore, horticulture is important for health, wealth, hygiene and happiness.

Lecture 2: Nutrition value of Horticulture crops

From human nutrition point of view horticulture is most important to our daily living. Many of the
horticulture crops and their products find place in our meals and diet. Since most of Indians are
vegetarians, the incorporation of horticulture produce in daily diet is essential for good health.
Realizing the worth of fruits and vegetables in human health, Indian Council of Medical
Research(ICMR) recommended the use of 120 g fruits and 280 g vegetables per capita per day.

Human body requires vitamins, minerals, proteins, energy etc. for its health. All these are
supplied by horticultural crops. Fruits and vegetables are the chief sources of vitamins, minerals,
carbohydrates, fats, proteins etc.
Fruits and vegetables are recognized as protective foods as they are necessary for the
maintenance of human health.

Vitamins: These are the important constituents of fruits and vegetables and are indispensable
part of human diet. Although required in very minute quantities, they are absolutely essential for
the maintenance of health. The deficiency of any vitamin from the diet for considerable period
may lead to diseased state or disorder conditions. Fruits and vegetables supply several vitamins.
Vitamin-A: It is essential for normal growth, reproduction and maintenance of health and vigour.
It affords protection against cold and influenza and prevents night blindness. The deficiency of
this vitamin results in cessation of growth in young children, night blindness, drying up of tear
glands in the eyes, eruption of skin (Rashes on the skin) and brittleness of the teeth
Sources: Fruits-Mango, Papaya, Dates, Jackfruit, Walnut etc. Vegetables-Greens like palak,
spinach amaranthus, fenugreek, carrot, cabbage lettuce, peas, tomato etc.

Vitamin B1 (Thiamine): Tones the nervous system and helps in proper functioning of the
digestive tract. Its deficiency in human diet results in “Ber-beri”, paralysis, loss of sensitivity of
skin, enlargement of heart, loss of appetite ,loss of weight and fall in body temperature.
Sources: Fruits-Orange, pineapple, jack fruit, cashew nut, walnut, dry apricot, almond, banana
etc,.Vegetables-Green chilli, beans, onion, sweet potato, tomato (red), leaves of colocasia .

Vitamin B2 (Riboflavin): This vitamin is required for body growth and health of the skin. The
deficiency of this vitamin causes sore throat, anorexia cataract, and loss of appetite and body
weight and also development of swollen nose.
Sources: Fruits- Bael, papaya, litchi, banana, apricot, pomegranate, pear etc. Vegetables-
Cabbage, cauliflower, potato, peas and beans, methi, lettuce, asparagus, green chillies, leafy
vegetables etc,.
Vitamin -C (Ascorbic Acid): This vitamin promotes general health and healthy gums, prevents
scurvy disease which is characterized by pain in the joints and swelling of limbs (rheumatism),
bleeding of gums, tooth decay and keeps the blood vessels in good condition.
Sources: Fruits: Amla, guava, ber, citrus, strawberry, pineapple etc. Vegetables: Tomato, palak,
menthi, cabbage, green chillies, spinach, potatoes, peas and beans and carrot etc,.
Vitamin-D: This vitamin is necessary for building up of bones, preventing rickets and diseases of
teeth.
Sources: All green leafy vegetables are rich in this vitamin.
Vitamin-E: Has an important effect on the generative functions and promotes fertility.
Sources: Green lettuce and other green vegetables.
Vitamin-K: This vitamin prevents blood clotting

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Sources: All green leafy vegetables are rich in this vitamin

Minerals: Human body requires minerals like P, Ca, Iron, and Iodine etc. for maintaining good
health.
Calcium: It is essential for development of bones regulation of heartbeat, controlling blood clots
Sources: Fruits- Acid lime, Orange, Fig, Dried apricots, wood apple etc. Vegetables- Cabbage,
greens, beans, carrot, onions, peas, tomatoes, agati, spinach drumstick leaves etc.
Iron: It is required for production of haemoglobin and it is constituent of red blood corpuscles. Its
deficiency causes anaemia, smooth tongue, pale lips, eyes and skin and frequent exhaustion.
Sources: Fruits- Custard apple, Guava, Pineapple, Straw berry, Grape, Black currents, dried
dates etc. and vegetables like Carrot, Drumstick leaves, beans and agati etc.
Phosphorous: It is essential for maintaining the moisture content of tissues and for development
of bones.
Sources: Fruits-Guava, Grape, Jackfruit, Passion fruit, Orange and vegetables like Carrot,
Chilli, Drumstick leaves, Beans, cucumber and onion.
Proteins: These are bodybuilding foods. These are essential for growth of the body. The
deficiency of proteins in the body causes retarded growth and increases susceptibility to diseases
and causes lethargy.
Sources: Fruits- Most of the fruits are low in proteins except Guava and Banana.
Vegetables like peas and beans are rich in proteins.
Enzymes: These are required for controlling several metabolic activities in the body. Sources:
Papaya-Papain and Pineapple-Bromelin.
Fibre and roughages (Cellulose and pectin): Fruits and vegetables supply roughages
These are required for digestion and prevention of constipation.
Sources: Fruits contain low content of fibre. Guava and anola are better sources compared
to other fruits. Leafy vegetables are rich in fibre content
Energy foods: Fruits and vegetables contain Carbohydrates and fats there by supply energy to
human body. Those fruits (Banana, Dates, Apple etc.) and vegetables (Potatoes, Sweet potato,
Beans, Peas etc.), which contain Carbohydrates, are called as “energy Foods”. Nut fruits like
Walnut, Cashew nut and almond etc supplies proteins besides energy.

Lecture 3: Divisions of Horticulture-their definition with crop examples and their importance

Horticulture crops include fruits, Vegetables, flowers, plantation crops, Spices, condiments, Medicinal and
Aromatic crops etc. In addition to these, Horticulture also deals with raising of trees for shade, ornamental
and avenue purposes, planning and raising of ornamental gardens, parks and raising of seed and planting
material. Further, horticulture also deals with the utilization of horticulture produce and
improvement of horticulture crops.
1. Pomology: It is derived from two words i.e. “Pomum” meaning fruit and “Logos” meaning
discourse or study. So, pomology is study or cultivation of fruit crops.
E.g. Mango, Sapota, Guava, Grape, Banana etc.
Fruit: It is a developed and matured ovary with or with out accessory parts and which is generally eaten as raw.
2. Olericulture: It is derived from two words ie. “Oleris” meaning Potherb and “Cultra” meaning
cultivation. So, Olericulture literally means potherb cultivation. In the present days it is broadly
used to indicate the cultivation of vegetables.Eg. Brinjal, Okra, Tomato, Pumpkin etc.
Vegetable: It is any part of the herbaceous plant that is generally used after cooking as a principal part of the meal.
3. Floriculture: It is derived from two words i.e. “Florus” meaning flower and “Cultra” meaning
cultivation. So floriculture means study of flower crops.
In this there are again two sub-divisions. (3.1) Commercial Floriculture
(3.2) Ornamental Floriculture.
3.1. Commercial floriculture: Deals with the cultivation of flower crops grown on commercial
scale for profit (Income). E.g.: Rose, Jasmine, Carnation, Aster, and Marigold etc.
3.2. Ornamental floriculture: It deals with the raising of flower crops for ornamental, pleasure
and fashion purposes. E.g.: Dahlia, Zinnia, Cosmos, Hibiscus, Balsam, Nerium, Poinsettia,
Hollyhock, Gerbera, and Gaillardia etc.
4. Arboriculture: This branch deals with the raising of perennial trees meant for shade, avenue
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 or ornamental purposes. Eg.Polyalthia, Spathodea, Cassia, Gulmohar etc.
5. Plantation crops: Are those crops, which are cultivated in an extensive scale in large
contiguous areas, owned and managed by an individual or a company and whose produce is
utilized only after processing.Eg. Coffee, Tea, Rubber, Coconut, Cocoa etc.
6. Spices and condiments: This branch deals with the cultivation of crops whose produce is used
mainly for seasoning and flavouring dishes.
Spices: Are those plants the products of which are made use of as food adjuncts to add aroma and flavour. Eg.
Pepper, Cardamom, Clove, Cinnamon, All spice etc.
Condiments: Are those plants the products of which are made use of as food adjuncts to add taste only.
Eg.Turmeric,Ginger,Red chillies,Onion,Garlic etc.
Both spices and condiments contain essential oils, which provide aroma, flavour and taste and
they are of little nutritive value.
7. Medicinal and aromatic plants: It deals with the cultivation of medicinal plants, which provide
drugs and aromatic crops which yields aromatic (essential) oils.
Medicinal plants- are those plants, which are rich in secondary metabolites and are potential sources of drugs. The
secondary metabolites include alkaloids, glycosides, coumarins, flavonoides and steroids etc. Eg. Periwinkle, Opium,
Menthi, Cinchona, Dioscorea Yam, Belladona, Senna, Sarpagandha, Aswagandha, Tulasi etc.
Aromatic plants- are those plants, which possesses essential oils in them. The essential oils are the odoriferous
steam volatile constituents of aromatic plants. Eg. Lemon grass, Citronella, Palmrosa, Vetiver, Geranium,
Davanam, Lavendor etc.
8. Fruit technology: It deals with the processing and preservation of produce of horticulture crops.
9. Landscape gardening: It deals with the planning and execution of ornamental gardens, parks,
landscape gardens etc.
10. Nursery and seed production: It deals with the production of seeds and planting material of
horticulture crops on commercial basis.

Plants grown for aesthetic value are also included in horticulture. Though crops like potato,
cowpea and several condiments are grown as field crops they are included under horticultural
crops when they are grown as vegetables in small areas.

Lecture 4: Horticulture and Botanical classification – classification based on nature of growth habit, life
span, climatic requirement, growing season, continuation of growth, bearing behavior, water requirement,
light requirement, photoperiodic requirement, fruits classification based on types, edible part, ripening
behavior.

1. Classification of Horticultural Crops Based on Growth Habit and Physiological Character:

Growth habit and physiological character e.g. herbs, shrubs, climbers and creepers

I. Herbs: Herbaceous plants are those with more or less soft succulent stems. In Temperate climates the
tips die off after season’s growth but root remains alive and produce new stem and tops on favorable
conditions. Ex. Ageratum, Lawn Grasses.

II. Shrubs: Shrubs have no main trunk but a number of erect or semi erect stems are seen but do not
forms the main frame work. Ex. Hibiscus, Rose, Lantana, Acalypha, Nerium, etc

III. Trees: Trees are upright in habit and stems take the form of central axis. Ex. Mango, Sapota, guava,
Mandarins etc

IV. Climbers: Those plants that take support of neigbouring structures, as their stems are weak and climb
up are called climbers. Ex. Bougainvillea

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V. Creepers: Both woody and herbaceous have stems which are flexible and not in position to keep their
branches and leaves erect. They either spread on the ground or require some support whether alive or
manmade. Ex. cucurbit vines, Grape vines, Passion fruit etc.

2. Classification of Horticultural Crops Based on Life span of plants:

I) Annuals:

From the name it is clear that the plants live for one season or less. Annual plant is one which completed
its life cycle from germination to seed formation within one season and then dies usually as a result of
complete exhaustion of its food reserve in the process of reproduction. Mostly they complete their life
history in 3 to 6 months. They comprise of several of most beautiful and easily grown plants, widely
varying in from habit of growth and colour. Annuals are very effective, grown neither in pots nor in ground.
Particular annuals thrive best in particular period of the year. The annuals are conveniently grouped
according to season as follows. e.g. Mary gold, Aster, Salvia, Zinnia etc.

II) Biennials:
These plants usually requires two years or at least two growing seasons with more or less of a dormant
season or lasting season between two completed life cycle. Seed sown in spring or summer, and
vegetative growth is completed in first year and in the following spring, flowering and fruiting takes place.
Generally the period of growth is 6 to 9 months e.g. Gladioli, Dahlia.

No hard and fast line can be drawn between annuals and biennials crops like turnip, carrot, cabbage
and onion are classified as biennials.

III) Perennials:
Any plant that lives more than two years is a perennial e.g. Mango, Citrus. These crops are classified in
to two groups.

3. Classification of Horticultural Crops Based on Climatic Requirements (Particularly

Temperature)

Based on temperature requirements and response to different climatic conditions, horticultural crops have
been classified in to three main groups and these are: i) Temperate, ii) Tropical and iii) Sub-tropical

I. Temperate: Temperate plants are commonly found in cold regions enjoying a mild and temperate
climate. These plants endure cold and go to rest or dormancy by shedding of all their leaves during
winter. Ex. Apple, Plums cherry and almond etc.

II. Tropical: Tropical plants are those which do not tolerate severe cold but can tolerate warm
temperatures of about 1000F. Those plants need strong sunshine, warms, humidity and a very mild
winter. They cannot stand far against frost. Ex. Papaya, Banana and Pineapple.

III. Sub-tropical: Sub-tropical plants like Orange, Litchi, Fig, Mango and cashew nut are intermediate in
characters of Temperate and tropical. They need warmth and humidity and can tolerate mild winters.

The above classification, based on climatic preference of plants, is more or less arbitrary and no
sharp line can be drawn between these several groups. It however, indicates the broad difference in
climatic needs of various plants. This does not necessarily mean that a plant belonging to one zone does
not grow in other zones. For instances, annual crops of the temperate region like potato, knol-khol and
cabbage grow in tropical and sub - tropical regions also, but they come up well only in the winter season
than other climatic zones.

4. Classification of Horticultural Crops Based on Season

Horticultural crops are also classified according to the season in which they grow best. In our country we
have three main season.

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 i) The Summer season, which starts from March and lasts upto May.
ii) The rainy season from June to October and

iii) The winter season from November to February.

Rainy season crops are known as "Kharif" crops. These crops come up best when sown with the onset
of monsoon in May, June. Vegetables like Snake gourd, Lady's finger, Chilies and Beans comes under
the category.

Winter season crops are known as "Rabi crops". They are generally sown October, November.
Only a few annual crops thrive in the warm summer months between March and June in the plains. Leafy
vegetables, cluster beans, Brinjal, Cucumber, and Gourds are the common summer vegetables.

There are some vegetables like tomato, brinjal, beans and flowers like which grow all the year round, but
they come up best when there is optimum season. The yield of a crop is also dependent upon the time
of sowing.

5. Classification of Horticultural Crops Based on continuation of growth

I. Deciduous: the plants that are leafless or which shed their leaves during winter are referred to as
deciduous. e.g., Apple, Fig, Grape etc.
II. Evergreen:The plants whose leaves persist the year round or grow continuously all the year round
are known as evergreen. The evergreens actually lose their leaves annually but not until a new set
of leaves are developed. e.g., Arecanut, Coconut, Banana, Mango, Sapota etc.

6. Classification of Horticultural Crops Based on bearing behaviour: On the basis of bearing habit,
fruit trees are classified in to 5 categories to facilitate cultural operation like pruning, skiffing, heading back
etc.

I. Terminal bearing
a. Bearing on new growth Ex. Loquat, Bael, Jackfruit, Pecanut
b. Bearing on old growth Ex. Mango, Litchi,
II. Axillary bearing
a. Bearing on new growth Ex. Grape, Ber, guava, Phalsa, Aonla, Fig, Sapota, Karonda, etc.
b. Bearing on old growth Ex. Apple, Pear, Peach, Plum, Tamarind, etc.
III. Mixed bearing Ex. Pomegranate, Citrus

7. Classification of Horticultural Crops Based on water requirement:

I. Hydrophytes: Those plants which grow partially or fully submerged in water.
Ex. Banana
II. Mesophytes: Plants which grow in situation where water is neither abundant nor scarce.
Ex. Mango, Guava, Citrus, Aonla, Custard apple, Apple, etc
III. Xerophytes: Plants which grow in extremely scarce condition of water.
Ex. Ber, Kair

8. Classification of Horticultural Crops Based on light requirement:

Heliophytes: Plants which grow in open sunny situation.
- Sun-loving (light saturation at 5000 foot candles
Ex. Banana, chrysanthemum, cucurbits, eggplant, papaya, peanut, sugarcane.
Sciophytes:- Plants which grow in shade
-shade-loving (light saturation at 500 foot candles) - Ex. Ginger, Ferns, coffee

9. Classification based on Photoperiodic requirement:

I. Long day plant: Require light period of 12 hours or less. Ex. Strawberry, Pineapple
II. Short day plant: Require light period of 12 hours or more. Apple Pineapple, Sweet Potato,
III. Day neutral plant: The flowering in many plants does not depend on the photoperiod.
Ex. Papaya, Guava, Sweet pepper.

10. Fruits classification based on types:

Three main types of fruits
I. Simple Fruits
10
 II. Aggregate Fruits (Etaerio)
III. Composite Fruits (Multiple)

Simple Fruits
These fruits develop from a single matured ovary in a single flower. Apple, banana, cherry pear, plum,
tomato are few examples of simple fruits. The simple fruits are classified into the following categories:
 Drupes: These are also known as stone fruits since it contains a very hard seed inside the simple
fruits. For eg., plum, cherry, peach.
 Berries: These type of fruits have a single seed in the center and are very juicy. Ex., grapes,
blueberries.
 Pomes: Such fruits bloom from trees. Ex. apple, papaya
 Hesperidium and Pepos: They are slightly similar to the berries and include fruits such as
watermelon, citrus fruits.
Aggregate Fruits
These fruits develop from a number of matured ovaries formed in a single flower. Individual ovaries are
called “fruitlets.” Blackberry, raspberry, strawberry are few examples of aggregate fruits.
Composite Fruits
These fruits develop from a complete inflorescence. these are also known as multiple fruits. Composite
fruits are of two types:
 Sorosis: These are found in mulberry, jackfruits and pineapple. They develop from catkin, spikes
and spadix type of inflorescence.
 Syconus: This develops from hypanthodium type of inflorescence. Ex.Fig

11. Fruits classification based on edible part:

I. Mesocarp and endocarp: Banana , amla
II. Mesocarp and epicarp: Jamun and phalsa
III. Pericarp: custard apple, ber, date palm
IV. Mesocarp : Mango, sapota, Papaya
V. Endosperm: Coconut
VI. Fleshy thalamus: Apple, pear
VII. Cotyledon: Cashew , Almond
VIII. Succulent placenta: Bael
IX. Fleshy receptacle: Fig
X. Aril : Litchi, Pomegranate
XI. Juicy placental hairs: Citrus
XII. Thalamus & pericarp: Guava
XIII. Fleshy peduncle: Cashew apple
XIV. Bracts/Perianth: Jackfruit, Pineapple
12. Fruits classification based on ripening behavior:
I.Climacteric: Sharp rise in respiration rate after harvesting Ex.Mango, Guava, banana, Fig etc
II.Non climacteric: Steady respiration at the time of harvesting Ex. Grape, Citrus,Pineapple, Pomegranate

Lecture 5: Climate and Soil requirements for Horticultural crops -Temperature, Humidity, Wind, Rainfall
and Solar Radiation - cultivation of horticultural crops in different agro-ecological zones in India.

1.Temperature: It is an important determinant of plant growth. High as well as low temperatures

influence the growth of plants. Broad leaved, ever green plants are very much susceptible to low
temperature. Fall of temperature below 5OC put a strain on the survival of such plants. Deciduous
plants by their adoptive mechanism to shed foliage are better able to tolerate low temperature.
Such plants pass their lives in dormant stage during winter. Generally, a temperature range of 20
- 30OC is considered ideal for majority of tropical and subtropical plants. Temperate plants require
chilling winter. In majority of temperate fruit plants, flowering commences subject to fulfillment of
chilling temperature ranging from 2OC to 7OC.High temperature above 40OC causes scorching in
plants. The leaves show burning symptom along tip and margin. High temperature causes bolting
and seed formation in spinach and lettuce. Development of red colour in oranges is governed by
low temperature. More severe winter favours discontinued synthesis of chlorophyll and unmasking
of carotenoids which imparts red colour to oranges. The optimum temperature for most of the
plants varies in the range of 22OC to 27OC. High fluctuation in day and night temperature badly

11
influences the growth and production of plants.

2.Humidity: It is a crucial component of climate affecting growth and production of crop. Humidity
is essential for growth of the plants and qualitative development of the fruits. The kharief plants
and vegetables grow fast with abundant humidity during monsoon season. The colour, TSS (total
soluble solids), sugar and acid blend is bettering in dry atmosphere having very little humidity. The
oranges grown under high humidity have thin rind and more juice. Low humidity favours better
colour development in oranges. High humidity favours resurgence of diseases and pets also. High
humidity during March causes powdery mildew disease in mango. Fruit fly incidence is more in
mango if there is high humidity in atmosphere at the time of fruit ripening. Fluctuation in
atmosphere humidity is the main attribute behind cracking of fruits. Under less humid conditions
the fruit skin is smooth, thin and shiny and it is important where the fruit skin is edible like Guava,
ber, apple etc.

3.Wind: High velocity and hot winds cause heavy damage to fruit trees. They cause breakage of
limbs of fruit trees. High velocity winds also cause shedding of flowers and dropping of fruits. Dry
winds bring scorching and torning impact on the leaves of banana. The increasing wind velocity
retards the activity of pollinators. Bee activity is maximum when wind is still, gets little reduced
when wind is 2-3 km per hour, gets greatly reduced when wind velocity is 25 km per hour and their
activity is altogether ceased when the wind velocity is 40 km per hour.In wind storm, spray of
pesticide and other chemicals become difficult.

For successful cultivation of fruit crops, raising of dense windbreak rows around the orchard is
necessary. The trees like eucalyptus. shisham, casuarina, seedling mango, and jamun may be
used as wind breaks.
4.Rainfall: The amount and distribution of rainfall is important factors in growth and development
of crop. Rain at the time of flowering washes out pollen grains and greatly reduces the fruit set. A
year of normal rainfall creates conducive condition and yields better growth and harvest of plant.
The fruits like guava, pomegranate, ber and sapota in which flowering synchronizes to rainy
season, normal rainfall brings bumper harvest. Water is required at different stages of plant
growth. Water shortage at the time of early growth, bud differentiation, blossoming, and fruit set
and development results in undesirable effect. Rains before harvesting cause softening of fruits
in banana and date palm and induce infection of fruit fly in guava and peaches. It is generally
observed that fruits are more juicy where they mature during rainy season due to high atmospheric
humidity. Fruits that mature during rainy season contain less sugar and more acid than fruits
maturing during dry season. Keeping quality of fruits and vegetables developing under high
atmospheric conditions may not be good.
5.Hailstorms: These causes great damage to the fruit crops. Occurrence of hail at the time of
flowering and fruit maturity is very disastrous because flower and fruit drop is heavy and the
growers get poor returns for their produce. For successful cultivation of fruit crops, only those
areas where hailstorms don‘t occur should be selected.
6.Solar radiation: It is the primary source of energy to plants. For the transformation of light
energy to chemical energy leading the production of photosynthates, solar radiation is must.
Orchard, located on southern side of the slope receiving better amount of radiation, bears better

12
yield than other side. The periphery and top most portions of plants are more productive due to
better and direct absorption of solar radiation. Training and pruning of plants are maneuvered in
a way; so that the plant may be better able to absorb more solar radiation required for good
productivity.
Agro-climatic zones: These zones are defined by major climate and the length of the growing
period, or moisture availability period. They are suitable for a specific range of crops and cultivars.
Agro-ecological zones: These zones are defined by climate, landforms, soils, and/or land cover.
They are carved out of agro-climatic zones and have a specific range of potentials and constraints
for land use.
The NBSS & LUP (National Bureau of Soil Survey and Land Use Planning), Nagpur, delineated
the country into 21 agroecological regions, using physiography, soils bioclimatic types and growing
periods.
Growing period (GP) was based on water balance starting with period having precipitation 0.5
excess of evaporation (PET) ending with utilization of 100 mm of stored soil moisture once
precipitation falls below PET.
Zone Arid zone Semi-arid Sub-arid Humid Perhumid zones or
region zone zones permanently humid
zone
Growing 90 days 90-150 days 150-210 210-270 >270 days
Period days days
(days/year)

Agro ecological zones delineated in this system are comprehensive and can be used for the
delineation of horticultural and plantation crops cultivation added with the data from field
experiments considering their perennial nature, differential response to soil moisture for growth,
production and quality added with disease and pest problems.

No. Zone name Regions occupied Special Crops grown

characters
1 Western Himalaya western cold arid , almond, walnut
Himalayas shallow ,pecan nut
covering Ladakh skeletal soils Chinese ber and
and Gilgit districts and length of deciduous
GP < 90 days pomegranate
2 Western Plain and Kutch Western parts of hot arid and Date palm, citrus,
Peninsula Rajasthan ecoregion grape, ber and aonla
southern parts of with desert
Haryana and and saline
Punjab, the Kutch soils and GP
peninsula and <90 days
northern parts of
Kathiawar
peninsula
3 Deccan Plateau hot arid Raichur and hot arid, Citrus (sweet orange
ecoregion Bellary in mixed red and acid lime),
Karnataka and and black mango, grape, ber,
Anantapur in soils and GP pomegranate and
Andhra Pradesh < 90 days sapota
4 Northern Plain and Central northern plains, hot semi arid Citrus fruits, guava,
Highlands central highlands with alluvium- mango and low-
and Gujarat plains derived soils chilling stone fruits
and GP 90-
150 days
5 Central (Malwa) Highlands western parts of hot semi-arid Ber, pomegranate,
and Kathiawar Peninsular Madhya Pradesh, ecoregion aonla, tamarind,
13
 eastern parts of with medium guava, citrus fruits,
Rajasthan and and deep mango and sapota,
Gujarat black soils coconut, oil palm,
and GP 90- cashew and black
150 days pepper, All vegetables
except cole crops
6 Deccan Plateau, hot semi- Maharashtra, shallow and Maharashtra, northern
arid northern parts of medium parts of Karnataka
Karnataka and (inclusion of and Andhra Pradesh,
Andhra Pradesh deep) black Coconut, arecanut, oil
soils and GP palm, potato and
90-150 days onion
7 Deccan Plateau and major part of hot semi-arid Sapota, custard-
Eastern Ghats Andhra Pradesh ecoregion apple, mango,
with red and banana, citrus fruits,
black soils guava and
and GP 90- pomegranate and
150 days especially Grape
occupies a significant
position
8 Eastern Ghats (TN Deccan plateau, hot semi-arid Mango, sapota,
uplands) and Deccan Tamil Nadu ecoregion guava, ber, aonla,
Plateau uplands and with red grape, banana,
western part of loamy soils tamarind and citrus.
Karnataka and GP 90-
150 days
9 Northern Plains northern Indo- hot sub- Mango, guava, citrus
gangetic plains humid fruits (limes and
ecoregion lemon), papaya and
with alluvium- low-chilling stone
derived soils fruits
and GP 150-
180 days
10 Central Highlands (Malwa districts of Raisin, hot subhumid Ber, pomegranate,
and Bundelkhand) Sagar, Bhopal, ecoregion aonla, bael and
Sahore, with medium mango
Shahjahanpur and and deep
Hoshangabad black soils
and GP 90-
150 days
11 Deccan Plateau and Bundelkhand hot sub- Besides high quality
Central Highlands humid mandarins, it is
(Bundelkhand) ecoregion potential growing
with mixed region for guava,
red and black sapota, mango, ber
soils and GP and pomegranate.
150-180 days Cashew and seed
spices
12 Eastern Plateau Chhattisgarh hot sub- Mango, citrus fruits,
(Chhattisgarh) region humid cashew nut, guava,
ecoregion papaya and
with red and pineapple,
yellow soils
and GP 150-
180 days
13 Eastern (Chhota-Nagpur) Eastern Chhota hot sub- Mango, guava,
Plateau and Eastern Ghats nagpur plateau humid banana, papaya,
and Eastern ecoregion jackfruit, pineapple,
Ghats with red cashew nut
loamy soils
and GP 150-
180 days
14 Eastern Plain UP, Bihar hot sub- Best litchi fruits are
humid grown in this region.
ecoregion Mango, jackfruit,

14
 with alluvium- guava, bael, aonla,
derived soils acid lime and banana
and GP 180- are predominant fruit
210 days crops in this region.
Coconut and arecanut
are potential crops in
this region.
15 Western Himalayas Western warm sub- apple, pear, peach,
Himalayas humid plum, apricot, and
(inclusion of almond
humid)
ecoregion
with brown
forest and
podzolic soils
and GP 80-
210 days
16 Assam and Bengal Plains Asom and West hot humid Banana, pineapple,
Bengal plains ecoregion mango and sapota
with alluvium- are predominant fruit
derived soils crops although litchi is
and GP < 210 also grown in sub-
days zones of the region.
Citrus fruits are also
grown especially in
Asom valley. Guava,
aonla and bael also
have potential in the
region.

17 Eastern Himalayas West Bengal, warm brown and red hill

northern parts of perhumid soils and GP < 210
Arunachal ecoregion days
Pradesh and with brown
Sikkim and red hill
soils and GP
< 210 days
18 North-Eastern Hills Nagaland, warm Citrus fruits, banana
(Purvanchal) Meghalaya, perhumid and pineapple are
Manipur, Mizoram ecoregion predominant fruit
and south Tripura. with red and crops
lateritic soils
and GP < 210
days
19 Eastern Coastal Plains Cauvery delta to hot sub- mango and banana,
Gangetic delta humid pineapple, Coconut,
ecoregion arecanut, cashew,
with alluvium- black pepper and
derived soils seed spices
and GP150-
210 days
20 Western Ghats and Sahyadari and hot humid sapota and cashew
Coastal Plains Western coastal perhumid nut, banana,
plains of ecoregion pineapple and mango
Maharashtra, with red,
Karnataka and lateritic and
Kerala alluvium soils
and > 210
days
21 Islands of Andaman- Andaman and hot perhumid Coconut is
Nicobar and Lakshadweep Nicobar and ecoregion predominant crop
Lakshadweep with red along with banana.
loamy sandy Pineapple,
soils and GP mangosteen, sapota
< 210 days and mango are

15
 potential crops in this
zone
 Application of agro ecological zones for planning the cultivation of horticultural and
plantation crops is directed towards improved production and productivity. But database is
not sufficient to delineate their cultivation. Since there is a significant variability within the
zone, micro-level planning based on field performance would be required for gainful
utilization of agro ecological zones.
 Wider adaptability, climatic acclimatization, response to production system and wide
genetic base of horticultural and plantation crops are advantageous for extending the area
under different zones for harnessing the maximum potential.
 In addition to soil and climatic conditions, incidence of diseases is also required to be
considered while delineating cultivation of these crops.

Lecture 6&7: Planning of Orchard – definition of orchard, orcharding, garden, plantation, estate - Principles
of orchard establishment- types of orchards – advantages and disadvantages with examples - Points to be
considered for Selection of site for establishment of orchard.

Establishment of an orchard is a long-term investment and deserves very careful planning by

following all the principles in sequence. There are 4 main principles have to be followed for
establishment of an orchard.
I. Selection of site
II. Preliminary Operations For Establishment Of An Orchard
III. Planning Of Orchard
IV. Steps In Establishment Of An Orchard

Few terms we have to learn to understand the different principles of orchard establishment
Orchard: refers to an area where intensive cultivation of fruit crops is done. Or it is an area where fruit
crops like mango, citrus, papaya, banana etc. are cultivated. Or it is an enclosed area where a fruit /group
of fruit trees are grown.
Orcharding: refers to growing of fruit plants in an orderly manner and maintain them for successive
economic returns.
Garden: The term garden refers to fruit farm, where sophisticated agro-techniques are employed for
commercial cultivation. Eg: Grape garden (Viticulture).
Specific crops: 1. Vineyard/vinery — grape garden
2. Pinery — Pineapple
3.Orangery—Orange garden (Citriculture)
Plantation: refers to a fairly large area where cultivation is done with a particular type of fruit crop.
Eg: Mango plantation, apple plantation, coconut plantation etc.
Estate: refers to large area (more than 1000 acres) of sole crop cultivation. This terminology was used in
earlier days (British empire). Eg: Coffee estate and Tea estate.

I. Selection of site: The following factors are to be considered before selecting a site for an
orchard.

16
1.Climate: The climate of the locality should be suited to the fruits, or the fruit chosen should be
suited to the climate. Enquires should be made on the following points to assess how climate
affects the fruits intended to be grown.

I. Experience of the fruit growers and research stations in the locality regarding the
acclimatization of the fruits under consideration.
II. The seasons of heavy rainfall, hail storms and hot winds.
III. The seasons and intervals of cyclones, heat waves, gales and other catastrophic features

2. Soil: Few prospective sites should be examined for both physical and chemical properties. For
this purpose profile pits of 2m depth should be dug in each representative part of the site as
suggested by external appearance, Samples should be collected and analyzed for deciding the
choice. Soil samples must be analyzed to know the suitability of soil for growing fruit crops. Soil
analysis gives information on the type of soil, its fertility; its pH value etc. As far as possible flat
land should be selected. There should be no hard pan up to a depth of 2m.

3. Irrigation facilities: Most of the horticulture crops are raised under irrigation. So the water
facilities should also be taken in to consideration (quantity and quality). Water table should be
below 2 m depth.

4. Nearness to the market: Saves the over head charges in transport and gives close touch with
market tastes (in the case of market gardens).In most cases a large percentage of the retail price
of fruits is accounted for by transport charges. The hill bananas and the apples of Kulu valley are
produced cheap but they are sold at high prices on the plains owing to heavy cost of transport.

5. Transport facilities: Fruits being perishable cannot be moved for long distances with out quick
and refrigerated transport. Bananas from the south are not reaching northern market in our own
country owing to the absence of refrigerated transport. But under refrigerated conditions, they can
be transported to longer distances. So; the orchards must be located where there is quick
transport, preferably a refrigerated transport system.

6. Power (electricity) supply: It would be a great advantage if electric power lines are running
in the proximity of the area as it can be tapped easily.

7. Proximity to established orchards: It is an added advantage if the site is in proximity to the

already established orchards because of compactness of areas of production facilitates provision
of transport and storage facilities. It also enables formation of co-operative societies and other
associations which can collectively own grading and spraying machinery and other costly
equipment including storage facilities. If there are compact blocks of single crop say citrus,
banana, mango etc. the spread of diseases and pests are more.

In selecting a site close to other orchards, one must make sure that they are free from devastating
pests and diseases like citrus scale, canker, panama disease of banana, the tristeza disease of
citrus.

8. Availability of labour: Large orchards are started often in out of the way places and forest
areas away from populated centres.It would therefore be necessary to ensure that adequate
labour is available for orchard operatins.This point is of important in plantation crops particularly.

17
9. Social factors: These assume importance when large contingents of labour and managerial
staff are to be employed as plantations or large orchards. They should be provided with medical
and educational facilities, so that, they are content and stick on to the jobs.

10. Presence of nurseries close by: It is an advantage if the nurseries are close by to the
selected site for selecting the plants for the orchard after studying the scion parents personally. It
will also help to get cheap and quick transport of plants which will ensure better establishment.

11. Cost of the land: Cost of the land comes up for consideration when all the other requirements
listed above have been satisfied. It should never be the prime consideration in the choice a little
extra cost paid for the foregoing amenities is more than repaid in the long run.

II. Preliminary Operations For Establishment Of An Orchard

After selecting the suitable location and site, some preliminary operations have to be done. Trees
are felled without leaving stumps or roots. The shrubs and other weedy growth are also
cleared.Deep ploughing is essential to remove big roots. The lands should be thoroughly
ploughed, leveled and manured. Leveling is important for economy of irrigation and preventing
soil wash. In the hills, the land should be divided into terraces depending upon the topography of
the land and the leveling is done within the terraces. Terracing protects the land from erosion. If
the soil is poor, it would be advisable to grow a green manure crop and plough it in situ so as to
improve its physical and chemical conditions before planting operations are taken up.

III. Planning of Orchard: It is of great advantage to prepare a plan of the orchard in advance, be it a home
or market garden or a commercial orchard. A detailed survey of the site is carried out including the levels
and a good map to scale is drawn. A full knowledge of the fruits to be grown and their cultivation is also
prerequisite for efficient planning.
The guiding principles in the preparation of plan are:

1) The orchard should be managed most profitably

2) It should present as attractive look as possible.

The following general principles may be borne in mind while drafting a plan and as many of them
as possible should be fulfilled. It should be recognized that not all of them can be adopted in every
case.

1. If the entire area is not of the same type of soil, each fruit should be allocated to the soil type it
prefers.
2. The irrigation sources should be marked and channels indicated along gradients with a view to
achieve most economical conduct of water.
3.Irrigated fruits should be close to the source of irrigation to avoid long irrigation channels and
consequent loss of water during conduct.
4. Tall wind breaks should be planted especially on the sides from which high winds are expected.
There should be adequate clearance between the wind breaks and the crop.
5. Roads should be planned to occupy the minimum space consistent with economy of transport
of orchard requisites and produce. The space between the wind break and the first row of fruit trees
may often be utilized for roads and canals etc. with advantages.
6. Drains should follow the gradient of the land, should be as straight as possible and concealed
from the visitors, if possible.
7. When varieties with pollen preferences are planted they should have the pollenizer in an adjacent
block or in alternate rows so as to ensure good crop set.

8. Fruits which ripen at the same time should preferably be grouped together to facilitate easy

18
watching and harvesting.
9. Assign rear areas for tall trees and the front for shorter ones will besides facilitating watching,
also improves the appearance of the orchard. The orchard should in general present an aesthetic
appearance so as to provide marked attraction.
10.The spacing adopted should be the optimum.The spacing allowed is usually such that the fringes of the
trees will just touch one another cutting out light but should not interlock.With in reasonable limits, closer
spacing gives more yields in the earlier age. But in later life, the trees tend to grow taller than broad resulting
in difficulty in pruning, spraying and harvesting. They also suffer from root competition inadequate nutrition,
fewer fruits which tend to be smaller with comparatively poorer in colour development. So, adoption of
closer spacing to accommodate more plants per acre proves to be a false economy in the long run. The
spacing given to fruit plants depends on the following factors.

a) The habit of growth of the plant: The spacing being equal to the spread of
the plants.
b) Rainfall: In the case of rain fed crops closer spacing is given in lighter
rainfall areas than in heavy rainfall areas.
c) Nature of soil: Trees on stiffer soils may be given less spacing as both their top
and root spread are limited in such soils.
d) The root stock: Root stock influences the spread of the trees and to that extent
determines the spacing to be adopted.
e) Pruning and training
f) Irrigation system.
g) The method of layout should be fixed in advance so that the no. of plants
required is worked out and arranged for.

Types of Orchards: There are various types of orcharding

1. Orcharding with single variety of a particular fruit crop:

Eg: Mango orchard exclusively Alphonso variety. ,Pomegranate orchard of Kesar variety,Guava
orchard of Sardar variety.
• Advantages:
1. Purity of the variety can be maintained.
2. Convenient for planning and management.
3. All the trees come to harvest at the same time.
• Disadvantages:
1. The variety may be incompatible (which leads to poor fruit set).
2. The variety may be susceptible to pest and diseases.
3. The variety may be irregular like Alphonso variety.
4. The variety may not satisfy all consumers.
2. Orcharding with different variety of fruit crop:
Eg: Mango orchard - Alphonso+ Kesar+Pairi, Sapota orchard - Cricket ball+ Kalipatti, Grape -
Thomson seedless+ Sonaka +Sharad seedless.
• Advantages:
1. If one variety fails for some reasons other variety will give some returns/income.
2. Problem of self incompatibility can be overcome.
3. It can help in supply variety of fruits during different periods and to cater the needs of
different customers.
• Disadvantages:
1. Purity of variety may be affected.
2. Management and harvesting varies.
3. Mixed orchard with different fruit crops of almost equal life span:
Eg: Mango+Sapota+Guava, Tamarind+Ber+Annona+Aonla, Fig+Pomegrante+Ber+Lime,
Papaya+Banana+Pineapple.
• Advantages:
1. More than one crop may be available on the same piece of land.
2. If one crop fails other crop will come to rescue and maintains continuity of income.
3. Year round income.

19
 • Disadvantages:
1. Management becomes very difficult.
2. Problems of pest and diseases.
4. Orchrding with intercrop:
• This system involves incorporation of another species (fruit/ vegetable) in between the
interspaces of main crop.
• This system uses the open space available during pre-bearing period of main crop. The
intercropping is discontinued once the main crop completely covers the canopy.
• The intercrop selected should have the following characters.
1. Should be compatible with main crop in their water, nutrient and soil requirement.
2. Compact stature and should not compete with main crop.
3. Short duration when compared to other perennial crops.
4. Should not act as an alternate host for pest and diseases.
Advantages:
1. Helps in getting additional income from the orchard during pre-bearing stage of main
crop.
2. It also acts as a cover crop and prevents soil erosion.
3. Suppress the weed growth in open space.
4. Efficient land utilization.

Eg: Banana, Papaya, Pineapple, Guava, Phalsa, Fig, Beans, Cowpea, Dolichos, Marigold,
Gaillardia, Aster etc.
5. Multistoried orchard:
Eg: Coconut + Black pepper + cocoa + pineapple.
Arecanut + Vanilla + Banana + Pinapple.
The principle involved in multistoried orchard is harvesting light at different height/stories. The
planting should be such that sunlight is harvested by different crops at different stories /levels /height
and there won’t be any competition for soil nutrients, moisture and sunlight because the spread and
distribution of roots at different crop component is distributed in different layers of the soil profile.
6.High density orchard:
High density aims at increasing the productivity per unit area by increasing plant population/unit
area by closer spacing.This has been successfully done in several temperate fruit crops like apple,
pear, peach etc. where there is availability of dwarfing rootstocks and plant response for training
and pruning and chemical regulation of size.
Eg : Apple 3X3 ---1111 plants/ha.
3X2 ---1666 plants/ha.
7. Dryland orchard:
Growing of fruit plants in drylands like arid and semiarid zones as rainfed crop. This concept is
gaining importance as several fruit crops have been identified for cultivation in arid and semi arid
regions. Eg: Ber, Aonla, Datepalm, Tamarind, Fig, Phalsa etc. With the advancement of irrigation
technology and efficient water harvesting and conservation some of high value fruit crops are also
being grown in arid and semiarid/ rainfed regions. Eg: Mango, Grape, Pomegranate etc.
8. Clonal orchard:
Orchard established from plants derived from single individual mother plants through vegetative
means.Eg: Clonal orchard of mango var. Alphonso.
Advantages:
• Plants will be uniform in growth, bearing habit and management practices.

Lecture 8: -Clearing the Land, Levelling, Fencing, Wind breaks, Selection of Plants from the nursery,
Season of Planting, Planting and Healing inn.

After the selection of the site and drafting the plan, next comes the establishment of an orchard
with fruit plants. For this, the selected site should be thoroughly surveyed for studying its size,
topography, flow of irrigation water, drainage and fertility gradients. The positioning of main and
subsidiary roads, wells, wind breaks etc.should be planned clearly.

IV.Steps in establishment of orchard

1. Clearing of the land: Preparation of the soil depends largely on its condition, previous history
and grower‘s plans. If the land has been under cultivation and has been well maintained, nothing
20
further may be required. On the other hand if the site is a new one and was never under cultivation
earlier, much has to be done well in advance for planting. If the land is a virgin land i.e. it is not
under cultivation previously, the existing vegetation is to be cleared. Standing trees, shrubs,
bushes etc. should be cut down and uprooted along with the stumps and removed. No vegetation
should be left on the site. Otherwise, they may shade the young plants; compete for water, light
and nutrients. Further, their removal at a later date is expensive and risky. All the stumps and roots
may be removed. Otherwise they may harbour white ants, termite hills, diseases etc. and spread
to the new plants. Along with vegetation, stones, rocks and ant hills, termite hills etc.should be
removed.

2. Leveling: Leveling is important for efficient irrigation, drainage to check soil erosion and also
for improving appearance. If the land is sloppy contouring (if the slope is 3 to 10%) or terracing (if
the slope is >10%) is to be done. During leveling sub soil should not be exposed.

3. Fencing: Fencing is necessary to protect trees from stray cattle, human trespassing and also
for attractiveness. The fence may be of stone, barbed wire or live fence. Growing of live fence is
an expensive one. At the initial stage it may be cheap but afterwards the maintenance is costly.
Live fence needs periodical punning or trimming to shape and also to control their growth and
encouraging more branching. This is one of the costly items of the orchard cultivation.

Characteristics of a good fence plant:

Drought resistant
Easy to raise from seed
Quick growing
Should have dense foliage
Should stand severe pruning
Should not be hard to secature
Should be preferably thorny
Live fences are sown at the commencement of rainy season to minimize irrigation. They are
dibbled in 3 rows; 20-30 cm apart in a trench dug 60cm deep and manured soil.
Examples of non-thorny fence plants: Tamarind, Thevitia, Lawsonia, Casuarina, Gliricidia etc.
Examples of thorny fence plants: Agave, cactus, Prosophis, Commiphora barli, Inga dulcis etc.

4. Wind break plants: The wind breaks are provided to resist the velocity of wind which causes
loss of bloom, wind erosion and evaporation of moisture and to keep the orchard warm by checking
frost and cold waves. The beneficial effect of wind break is felt up to a distance equal to 3 times
its height.

The characteristics of a tree suitable as wind break are:

It should be fast growing

It should be easily estabishable
It should be able to acclimatize to the environment
Should have dense canopy
It should not harbour pests and diseases
It should be frost resistant
It should be drought resistant
21
 It can be propagated by various methods
Planting material should be easily available and cheap
It should have multipurpose uses like fuel wood, fodder etc.
It should with stand periodical pruning.

Wind Breaks

Some plants usually employed for growing as wind break plants are: Casuarina (Most effective in
open sandy soils), Pterocarpus santalimus (Redsanders), Erythrina indica (Requires pruning to
make tree top bushy),Cassia‘s and Polyalthia longifolia (Slow growing) are some trees which can
also be used. For mango orchards, seedling mangoes and polyembryionic mangoes may be
planted as wind breaks to provide chance seedlings and root stocks.

There should a spacing of 12m between the row of wind break and the first orchard row. This
space may be occupied by roads and drains. The wind break trees should be planted closer than
their spread so as to form a thick screen. A spacing of 5m is maximum for most plants.

5. Roads and drains: These are laid out according to the plan prepared in advance taking the
convenience and levels into consideration. Main irrigation channels also have to be plotted. Open
drains should be straight, running parallel to the gradient. Silt catching devices should be
employed in the drains. Covered drains should be filled with big stones at the base and smaller
ones over them and the top 12 inches should be covered with the orchard soil so as not to impede
ploughing and other operations.

6. Tillage: Tillage including sub soil should be done thoroughly at this stage, since it cannot be
done after planting without disturbing the roots of the trees.

7. Sowing green manure crops: A green manure crop is sown thick and uniformly all over the
area to be planted. Apart from the manurial value the crop reveals by its growth, infertile patches
of the land, so that they can be examined and suitable steps are taken for amending them.

8. Marking plant positions: The system of layout should be decided first. Then one of the fence
lines or a road should be chosen as the base line. In deciding the base line, due regard should be
given to appearance of the rows from the road along which the visitor or the manager is expected
to walk.

9. Digging and filling of pits: Generally the pits are dug 2 to 3 months in advance of planting i.e.
March to May. Allow the pits to weather. A planting board (a plank about 1.5m long or longer with

22
two end notches and a center notch) is applied to the marking peg by its central notch and two
pegs are driven at the end notches. Then the board and the marking pegs are removed and a pit
of 1-meter cube is dug. The two pegs driven at the end notches remain in position on either side
of the pit. All pits are dug similarly so that plant position is not altered at planting time. While
digging, the topsoil should be kept on one side and the bottom soil on another side separately as
the topsoil is somewhat fertile than the bottom soil.

While filling the pits, the topsoil is mixed with farmyard manure or compost, leaf mould or green
leaf and a kilogram of super phosphate. Then the pits are filled with the bottom layer of soil first
and then with the topsoil mixed with the manures. The soil after filling should rise about a foot
over the orchard level so as to allow for shrinkage on setting

10. Filling of pits: Filling is done a fortnight or two after digging pits. The pits are filled with a
mixture of Top soil; FYM, leaf mould and bone meal. Pits are filled a few inches above the ground
level for shrinkage and settlement.

11. Selection of plants from the nursery: Generally the plants are purchased from the nursery
well in advance. The grower should visit the nursery and select the plants. Plants are selected on
the basis of certain characters of the plants.

Branching: The main branches on the young plants become leaders on a grown up tree. These
branches arise on a plant at an angle (crotch).This crotch should neither wide nor narrow but it
should be medium i.e. 40-50O. If the crotch is wider splitting or breaking of limbs will occur because
of heavy crop load. If it is narrow (<30 O) forms weak frame work. So plants having medium
crotches are best. The branches on the trunk should not be opposite or in a whorl but alternate
with at least 15cm spacing.
Growth of the plant: The plants should be uniform in growth and is determined by uniform length
of internodes. For immediate planting, plants in active growth should not be selected because
they may wilt during transit and die on planting. Deciduous fruit plants should be planted when
dormancy is about to terminate. They put up new growth quickly and establish early.
Age of the plants: Growers generally prefer older plants believing that these plants come to
bearing early. For this there is no experimental evidence. Younger plants make up in a few years
and become equally vigorous and out grow older plants. So, no benefit of selecting older plants.
Choosing young plants have many advantages like cheaper in cost, easier to transport and they
withstand transplanting shock and easier to transplant.

Pests and diseases: Plants should be free from pests and diseases like scale insects, mealy
bugs, aphids, nematodes etc and diseases like canker, and viral diseases.
12. Lifting and packing: Before lifting of plants from the nursery the nursery is thoroughly irrigated
one day in advance for easy lifting of the plants without damage to the root system. Then the
plants are lifted carefully along with a ball of earth attached to the root system. The roots are
wrapped in straw or grass or covered with a gunny cloth and placed in a basket or a wooden crate
for packing. Depending on the size of the basket or crate 6-7 plants are kept for each basket.4-5
long bamboo splinter or wooden pegs are forked into the sides of the basket and tied at the top.
In between the plants and at the top of the basket after filling, the plants re covered with straw so
as to avoid falling during transit.

23
13.Season of planting: The distribution of rainfall in the tropics and subtropics and the break of
spring growth in temperate zone determine the season of planting. In tropical climate, most trees
are planted between July and December and few in January also. In general planting is done
during the monsoon in moderate rainfall areas and at the close of the monsoon in heavy rainfall
areas.

Planting should be done on cloudy days and preferably in the afternoons rather than in the
morning.

14. Planting: The planting board should be used at the time of setting the plants, so that they are
in a perfect line. The plants should be set in the soil to the same level as it was in the nursery. The
bud / graft joint should not be covered with soil. Plants should be irrigated once copiously to get
the soil particles to closely adhere to the roots and also to drive away the air around the roots
completely. The plants should be staked with a straight bamboo piece or other twig. Graft bandage
should be removed if not already done. Any buds on the rootstocks should be rubbed off.

15. Heeling inn: If the plants after transport are not directly planted in the field, they may be kept
in shade in a slanting position along the side of a trench moistening the ball of earth .They may be
left in this position till active growth commences by which time they should be planted in the field.
This process is known as healing inn.

Lecture 9: Planting systems- Lay out- Different systems of Planting -Square, Rectangular,
Quincunx, Hexagonal, and contour Planting with their merits and demerits

The arrangement of plants in the orchard is known as lay-out. The following points
need to be considered before choosing a system of planting.
 It should accommodate maximum number of plants per unit area.
 It should allow sufficient space for the development of each tree.
 It enables equal distribution of area under each tree.
 The intercultural operations such as ploughing,spraying etcare easily carried
out.
 It makes supervision more easy and effective.

Descriptions of the different systems:

(1) Square system:

24
  In this system a tree is planted at each
corner of a square what ever may the
Planting distance.
 The distance between row to row and plant
to plant is same.

Advantages

Most commonly followed and simplest of all and easy to lay out.
Irrigation channels and paths can be made straight.

The possibility of cultural operations in two directions is the greatest advantage

of this system

Better supervision of the orchard is possible as one gets a view of the orchard
from one end to the other.

Disadvantages

Comparatively less number of trees are accommodated in given area.

Distance between plant to plant and row to row remains the same and , hence,
certain amount of space in the middle of four trees is wasted.

(2) Rectangular system:

 Similar to square system, except that the

distance between plants in the row and
distance between rows is not the same
but different.
 Row to row distance is more than that
from plant to plant in the row.

Advantages

Intercultural operations can be carried out easily in the early stages.

Irrigation channel can be made length and breadth wise

Light can penetrate into the orchard through the large inter spaces between
rows.

Better supervision is possible.

Intercropping is possible.

25
Disadvantages

Intercultivation is some what difficult when the trees have fully grown.

A large area of the orchard between rows is wasted if intercropping is not

practised.

Less number of trees are planted.

(3) Quincunx or filler system:

 This is also known as filler or diagonal system.

 This is the modification of a square system of
layout distinguished to make use of the empty
space in the center of each square by planting
another plant is called filler tree. Generally the
filler tree will be precocious and shorter duration
and not be of same kind as those planted on the
corner of the square. Guava, phalsa. plum,
papaya, peaches, kinnow are important fillers.
They yield some crop before the permanent
trees come into bearing.
 The filler tree is removed when the main fruit
trees grow to full stature and start bearing.

This system is followed when the distance between permanent trees exceeds 8m or
more or where permanent trees are very slow in their growth and also take longer time
for coming to bearing. Eg. Sapota, Jackfruit.
Advantages

1. Additonal income can be earned from the filler crop till the main crop comes into
bearing.

2. The main advantage of this system is that the plant population is about double than
the square system.
3. Maximum utilization of the land is possible.

Disadvantages

1. Skill is required to layout the orchard.

2. Inter / filler crop can interfere with the growth of the main crop.

3. The greatest disadvantage of this system is that, it is difficult to carry out

intercultural operations on account of the filler tree.
4. Spacing of the main crop is reduced if the filler crop is allowed to continue after the
growth of the main crop.

(4) Hexagonal system:

26
 1. This is also called as equilateral system. Some
times a seventh tree is planted in the centre of the
hexagon, and then it is called septule system.
2. In this system the trees are planted in each corner
of the equilateral triangle.
3. This system differs from the square system in
which the distance between the rows is less than the
distance between the trees in a row, but the distance
from tree to tree in six directions remains the same.
4. This system is usually employed, where land
is expensive and is very fertile with good availability
of water.

Advantages
1. Compared to square system 15% more trees can be planted. It is
an ideal system for the fertile and well irrigated land.
2. Plant to plant distance can be maintained the same. More income
can be obtained.
3. This system permits cultivation in three directions.
4. The plants occupy the land fully without any waste as in square
system
Disadvantages
1. Intercultural operations become difficult.
2. Skill is required to layout the orchard.
3. This system is not generally followed because it is
difficult to adopt in practice in the field

27
 (5) Triangular system:

 The trees are planted as in square

system but the difference being
that those in the even numbered
rows are midway between those
in the odd rows instead of
opposite to them.
 Triangular system is based on the
principle of isolateral triangle. The
distance between any two
adjacent trees in a row is equal to
the perpendicular distance
between any two adjacent rows.
 However, the vertical distance,
between immediate two trees in
the adjacent rows, is equal to the
product of (1.118 x distance
between two trees in a row).

Merits and demerits:

1. This system is not much of practical importance.
2. Plants are not placed at equal distance from all sides.
3. When compared to square system, each tree occupies more area and hence it
accommodates few trees per hectare than the square system.

All the above systems are possible when the land is flat, plain or level, but not on uneven
lands and sub-mountane areas (hilly areas).On undulating lands and hill slopes different
types of planting systems are followed,Viz.,contour and terracing.

(6) Contoursystem:

It is generally followed on the hills where the plants are planted along the contour
across the slope.

 It particularly suits to land with undulated topography, where there is greater

28
 danger of erosion and irrigation of the orchard is difficult.
 The main purpose of this system is to minimize land erosion and to conserve soil
moisture so as to make the slope fit for growing fruits and plantation crops.
 The contour line is so designed and graded in such a way that the flow of water
in the irrigation channel becomes slow and thus finds time to penetrate into the,
soil without causing erosion.
 Terrace system on the other hand refers to planting in flat strip of land formed
across a sloping side of a hill, lying level along the contours.
 Terraced fields rise in steps one above the other and help to bring more area into
productive use and also to prevent soil erosion.
 The width of the contour terrace varies according to the nature of the slope. If the
slope becomes stiff, the width of terrace is narrower and vice-versa.
 The planting distance under the contour system may not be uniform.

 When the slope is <10% contour bunding is practiced and if the slope is >10%
contour terracing is practiced.
 In this system the trees are planted along the contour line at right angles.
 Cultivation and irrigation can be practiced along the tree rows only.

Advantages

This system can be adopted in hilly regions and in leveled land.

Contour system can control the soil erosion.

It helps simultaneously in the conservation of water.

Preservation of plant nutrients supplied by manures and fertilizers possible.

Contours form an easy path for movements on the hill slpes for carrying out
various orchard operations such as weeding, manuering, pruning, harvesting,
disease and pest control.

Disadvantages

Laying out of contour lines is difficult and time consuming.

Special skill is required to layout this system.

Special instruments are required for making contour lines.

The row to row distance will not be equal and adjustments may be required in
the plant to plat distance.

Rows are broken in to bits and pieces.

The no. of plants per unit area will generally be less than other system

Calculation of number of plants in different systems of planting

Square system of planting: Area of the land

Area occupied by a single tree

29
 100 m2
Rectangular system: Area of the land

Area occupied by a single tree

Quincunx system: Area of the land

X2
Area occupied by a single tree

(Double the no. of plants of a square system)

Area of the land

Hexagonal system = -------------------------------------
Area occupied by a single tree

In this system each tree occupies a parellogram area

Each parallelogram consists of 2 equilateral triangles.
Area of each parallelogram consists of 2 equilateral triangles.
Area of each equilateral triangle is 3/4 X a 2
Where a is the length of a side of a triangle ie. Spacing between the trees in a row.
So a tree occupies = 3/4 x a 2 x 2

30
Lecture 10: High density planting / high density orcharding – categories of HDP, Advantage, Components
of HDP, Methods of HDP- tree size control, use of dwarfing rootstock, training pruning, use of growth
retardents, impact of HDP in major fruits

Planting of fruit trees rather at a closer spacing than the recommended one using certain special
techniques with the sole objective of obtaining maximum productivity per unit area without
sacrificing quality is often referred as 'High density planting' or HDP. This technique was first
established in apple in Europe during sixties and now majority of the apple orchards in Europe,
America, Australia and New Zealand are grown under this system.

Based on plant population, HDP is termed as Low HDP with less than 250 trees/ha., higher HDP
with 500-1250 trees/ha and ultra HDP with more than 1250 trees/ha. Recently, super high density
planting system has been also established in apple orchards with a plant population of 20,000
trees per ha. Still dense population of about 70,000 trees/ha is followed in certain orchards and
this system of planting is referred as meadow orcharding as practiced in apple.

The exact limits of plant density to be termed as are not yet well defined. It varies with the region,
species, variety, rootstock, cost of planting material, labour and likely return from the orchard and
agro-techniques adopted for a particular crop.

High density planting is one of the improved production technologies to achieve the objective of
enhanced productivity of Indian fruit industry. Yield and quality of the produce are two essential
components of the productivity. High density planting aims to achieve the twin requisites of
productivity by maintaining a balance between vegetative and reproductive load without impairing
the plant health.

The underlying principle of high density planting is to make best use of vertical and horizontal
space per unit time and to harness maximum possible return per unit of inputs and national
resources. In India, the usefulness / vitality of this technology has been proved in an array of fruit
crops eg.; pineapple, banana, papaya, mango, apple and citrus.

Advantages:
1) It induces precocity/precocious bearing
2) Higher yields. The average yield in apple is about 5.0 t/ha under normal system
of planting and it is about 140.0 t/ha under high density planting.
3) Higher returns per unit area
4) Early returns
5) Easy management of orchard tress
6) Reduces labour cost resulting in low cost of production
7) Enables the mechanization of fruit crop production and facilitates more efficient
use of fertilizers, water, solar radiation, fungicides, herbicides and pesticides.

31
 Dis- advantages of high density planting:
1) HDP results in over crowding, over lapping not only in the tops, but also in
the root system and heavy competition for space, nutrients and water.
2) More important is build up of high humidity, lack of cross ventilation in the
orchard, which is more conducive for build up of pests and diseases.
3) Reduction in yield in the long run after 10-12 years of age.
4) Production of small sized fruits and poor quality fruits.
Methods of HDP

I. Control of tree size

II. Planting systems
Tree Size Control : is achieved by following techniques
1. Use of genetically dwarf scion cultivars:

Crop Genetically dwarf cultivars Desirable features

Mango Amrapalli Precocious & tend to bear regularly
Papaya Pusa Nanha Dwarf & tend to bear at lower height
Banana Dwarf Cavendish (AAA) High yielding with dwarf stature
Sapota PKM1 PKM3 Columnar tree shape Dwarf tree stature
Apple Spur varieties like Red Spur Bear on short stem, spurs; grow to 60-70% of standard cultivars
Chief, Oregon in vigour and bear more spurs and yield more
Cherry Compact Lambert, Meteor High yielding, self fruitful Dwarf
and North Star
Peach Redheaven Dwarfing & high yielding
2. Use of dwarfing rootstocks and interstock

Crop Dwarfing Rootstock

Apple M9, M26, M27, Bud.9, P22 & Ottawa3
Pear Quince C
Peach Siberian C, St Julien X, Prunus besseyi and Rubira
Plum Pixy
Cherry Colt and Charger
Ber Zizyphus rotundifolia
Citrus Citrangequat, Feronia and Severinia buxifolia
Guava Psidium friedrichsthalianum, P. pumilum
•Standard plantation on standard apple rootstocks ( MM106) at 5x5 m accommodate 400 plants/ha,
• Spur apple cultivar on standard rootstock MM111 at 4 x 4 m and semi dwarf MM106 and M7 at 3x3m
accommodate 1111 plants/ha.
• Non spur type cultivar on dwarf rootstock M9 spaced at 2 x 2 contain 2500 plants /ha.
3. Training and Pruning
•Pruning -dwarfing effect on the tree.
• Slow growing trees respond more favourably to pruning and training and can be maintained at a given
size and shape without sacrificing yield.
• Removal of apical portion - compact and bushy tree

32
• Mango, guava, litchi and most of the other fruit crops in India are evergreen and are seldom pruned.
• Pruning -to regulate crop in guava, ber and fig, and rejuvenation of old orchards in mango.
• Tree size control through pruning - limited to grape, apple and some other temperate fruits.
• Spindle bush raised on M9, M7 and M4 rootstocks -promising training system for HDP.
4. Use of growth retardants :
• Commercially adopted are CCC, Ancymidal, Paclobutrazol , B-9 (Phosphon D) and chloramquat.
• Paclobutrazol - gained commercial application in crop regulation in mango
5.Induction of viral infection :
•Not adopted commercially, – tree size can be reduced by inducing viral infection e.g. Citrus, apple .
• In apple, virus free rootstock series East MaIling Long Ashton (EMLA) are vigorous than their infected
counterparts.
6.Use of incompatible rootstock:
• Use of graft incompatible scion and stock also induces dwarfness. – not commercially exploited for this
end. • In ber, cultivars on Zizyphus rotundifolia, Z. nummularia induces dwarfness due to graft
incompatibility
II. Planting Systems:
• Aimed to achieve high assimilated production for its conversion into economic yield.
• Various planting systems adopted in fruit crops – square, triangular, quincunx, rectangular, hexagonal,
hedgerow ( single & double), paired planting and cluster planting.
• Square and triangular systems are followed – for HDP in mango, Kinnow, banana, papaya and
• Hedge row system in apple and pineapple in India.
Impact of HDP
• In mango, – Amrapali at 2.5x 2.5m in triangular system accommodation of 1600and – Dashehari at 3.0
X 2.5 m in square system -1333 plants per hectare,
• Increase in yield per hectare was 2.5 times in Amrapali than that of the low density orchards of vigorous
cultivar.
• In Dashehari mango, the average yield in high density is reportedly 9.6 tonnes compared to 0.2 tonnes
in low density planting.
• This yield can further be improved in alternate bearing cultivars like Dashehari , Chausa and Bombay
Green through the application of growth retardant like Paclobutrazol.
•In Citrus, Kinnow on Troyer Citrange and Karna khatta rootstocks could be planted at 1.8 x1.8.m and
3x3 m to accommodate 3000 and 1088 plants per hectare, respectively.
• In pineapple, population density of 63758 per hectare coupled with improved package of
agrotechniques result in increase in yield from 15-20 to 70-80 tonnes/ha.
45X60X150 cm – 15000
45X60X200 cm – 20000
25X60X105cm - 49,000

25X60X90cm -53,000 suckers per hectare.

Lecture 11: Propagation –Definition- Methods of Propagation-Sexual - Advantages

and disadvantages

Plant propagation refers to the multiplication of an individual plant or group of plants, which have
33
specific value to mankind. Perpetuation of plants is called propagation. It involves multiplication of
one plant into several plants –development of new individuals. New plants or new individuals are
required for establishing new plantings / new gardens/ new orchards.

Methods of propagation: Broadly grouped in to two. (a) Sexual and (b) asexual.

Sexual (Seed) Propagation

It refers to multiplication of plants by seed. In sexual process male and female gametes are fused
to produce seed. Meiosis division takes place in course of fusion and the chromosome numbers,
as in parents is reduced to half, which after fertilization becomes normal. In sexual propagation
during meiosis segregation, reassortment or rearrangement of characters takes place. So, the
plants thus produced may or may not be similar to their parents and the propagated plants may
also be different from each other. It is called as seed propagation, since the propagation is through
seed and also sexual propagation because sexes are involved

Seed is the result of fusion of male and female gametes. Seeds are fertilized ovules, containing
embryos resulting from the union of a male and a female gamete during fertilization. The embryo
in the seed gives rise to a new plant on germination. Plants that are produced from seeds are
called seedlings.

Advantages of Seed propagation:

1) Seedling trees generally live longer, bear more heavily and are hardier than
vegetatively propagated trees.
2) Seedlings are comparatively cheap, and can be more easily raised than
vegetatively propagated materials.
3) Plants which are difficult to propagate, e.g., papaya and phalsa by vegetative
method can only be propagated by seed.
4) In breeding for evolution of new varieties, the hybrids are first raised from the
seed and it is, therefore, essential to employ this method in such cases.
5) Seed propagation, some times results in the production of Chance seedlings
with superior characteristics, which may be of great benefit to the horticulture
industry.
6) Rootstocks, on which desirable scion variety is budded or grafted, are usually
raised from seeds.

7) Seeds of some fruits like citrus and mango varieties are capable of giving out
more than one seedling from one seed. They arise from the cells of the nucellus
and are called poyembyonic.The nucellar seedlings can be utilized for raising
uniform plants, if they can be carefully detected at the nursery stage.
8) Since most virus diseases are usually not transmitted through seed propagation.
Hence, it is useful in producing virus free plants.
9) Seeds also offer a convenient method for storing plants for a long time. Seeds
when kept properly may remain viable for very long periods.Eg. Indian lotus

34
 remains viable for over 1000 years.
Disadvantages of seed propagation:
1) Owing to genetic segregation in heterozygous plants, seedling trees are not
uniform in their growth, yielding capacity and fruit quality compared with
asexually propagated plants. Seedling trees are not usually true to type and show
variation.
2) Seedling trees take more time to come to bearing than grafted plants .For
example mango seedlings take 8 -10 years to come to bearing ,compared with
3-4 years for grafted trees.
3) Seedling trees, being very large, pose problems for efficient management of
orchard trees, i.e., harvesting, pruning spraying etc. become more difficult and
expensive.
4) It is not possible to derive the benefits of rootstocks, if the plant is not propagated
vegetatively by means of grafting or budding.
5) Continuous seed propagation leads to inferiority in the progeny.
6) Sexually propagated plants have long juvenile (pre-bearing) period.
7) Choice or chance tress or hybrid trees can not be multiplied true to type
because of segregation of characters.
8) Seeds loose viability with in a short period.Eg.Citrus, mango, jack, papaya,
jamun etc.

Lecture 12: Asexual - Advantages and disadvantages

Asexual propagation is called with different names -- Asexual propagation, Vegetative
propagation, Clonal propagation. Asexual propagation is reproduction by means of vegetative
parts of the plant such as roots, shoots, or leaves other than seed. In this propagation sexes are
not involved–hence it is called asexual propagation. It involves the use of any part of the plant,
other than seed i.e. vegetative parts –hence vegetative propagation.
The vegetative organs of many plants have the capacity (ability) for regeneration, to produce new
individuals.
For instance: (a) stem pieces (cuttings) produce root system
(b) Root pieces (root cuttings) develop root system.
(c) Leaves generate both roots and shoots.
Vegetative parts possess somatic cells. They divide (multiply) by mitosis –does not involve
reduction in chromosomal number, but involves the duplication of chromosome structure -the same
genetic constitution is seen in the resultant plants – no variation. Whatever the characters present
in the parent –the same are carried in the new plants i.e. duplicated without any change –true to
mother plant-variation is eliminated.

Advantages:

As there is no change in the genetic makeup of the plant propagated by this

method, the fruit plants propagated vegetatively are true to type,and, as a result,it
is possible to get uniformity in growth,yield and quality of fruit,which makes
harvesting and marketing easy.
Some fruits sucha as banana, pineapple and some guava varieties being
seedless, the only way of further propagation is vegetative method.
35
 Vegetaively propagated fruit trees come into bearing earlier.
Certain varieties of some fruit plants are susceptible to certain diseases.By
budding or grafting them on a resistant root stock, these varieties can be grown
with out pest or disease incidence.
Hardiness to cold and other unfavourable conditions sauch as drought can be
secured, e.g.orange do well on trifoliate stock in areas where frost occurrence is
frequent.
Trees can considerably dwarfed by using proper root stocks,e.g.,the apple
trees can be dwarfed by using MallingIX as the root stock.
Methods like bridge grafting or butressingcan be used for healing of the wounds
caused by rodents.
By top working the inferior quality fruit trees can be converted into superior quality
fruit trees.
As a fancy, it is possible to grow 2-3 varieties on the same plant, e.g; one can get
3-4 varieties of roses on various branches of the stock plant.

Dis-advantages:

1) No, new variety can be evolved by means of the vegetative method of

propagation.
2) Vegetative propagation in many cases is more expensive than seed propagation.
3) Vegetatively propagated plants are comparatively short lived. Lack of tap root
system in vegetatively propagated plants results in poor anchorage in the soil.
Consequently, such plants are easily uprooted in storms and or other such
severe conditions.
4) Vegetatively propagated plants are comparatively less hardy.
5) Transmit viral diseases from plant to plant.
Which method of propagation is the best?
Considering the merits and demerits of both the methods, particularly in fruit crops and other perennial
crops, vegetative propagation is more preferable than seed propagation because of uniformity (even in
delicate characters like shape, taste, flavour etc.) and precocity.

36
Lecture 13: Seed germination- Dormancy-Reasons for Seed dormancy, Methods to overcome
Seed Dormancy
Seed germination:
Seed is an embryonic plant surrounded with protective seed coat or covering and supplied with
stored food. It is the physiological process through which development of seed into a seedling takes
place when exposed to favourable environmental conditions. While germination radicle comes out
first followed by plumule. The radicle gives rise to the rootsystem of plant while the plumule gives
rise to shoot system

There are 3 factors which are associated with germination of seeds

i. Seed must be viable viz., embryo should alive
ii. Seed should be subjected to favourable environmental condition
iii. Internal conditions associated with seed which prevent the
germination have to be eliminated.
Categories of seed dormancy:
Dormant seed : Seed exposed to favourable environment for germination does not
germinate which implies the presence of dormancy.

Four groups of Dormancy

Group I: Seed coat dormancy
a) Hard seed covering, impermeable to moisture. Eg. Leguminoceae, Malvaceae
b) Hard seed covering resistant to embryo expansion eg. Walnut
c) Seed covering containing chemical inhibitors. These are by leaching with water eg.
Citrus. Cucurbits.
Group II: Seeds with morphologically undeveloped (rudimentary) embryos Embryos are not well
developed at the time of harvest and will grow before germination occurs. Eg. Palmae , Annona
Group III: Seeds with internal dormancy (endogenous)
Germination is regulated by the inner tissues of seeds – endosperm and inner
integumental layer. There are three groups in this category.

a)Physiologically shallow dormancy

This type is present is most freshly harvested seed and disappears with dry storage over a
period of days or months. It may be due to endogenous inhibitors in fresh seeds. Treatments
with GA, Kinetine, Potassium nitrate may be used to over come.

b)Physiologically intermediate dormancy

Moisture chilling stimulate germination. This is found in conifers and in woody plants.
Temperature just above freezing (2 to 7 oc) are generally most effective to break dormancy.

C)Physiologically deep dormancy

This will disappear with prolonged moist chilling. This is to regulate embryo and seed covering
to facilitate germination. Eg.Temperate zone herbaceous plants.

Group IV: Combined or double dormancy

Both seed coat (external) dormancy and embryo (internal) dormancy occur. Here treatments
must be given in sequency. Eg. Woody trees and shrubs of temperate region.

Pre-conditioning of seeds or breaking dormancy:

I. Scarification :
1) Mechanical scarification
This is done to modify hard or impervious seed coats. Scarification is a process of
breaking or scratching or mechanically altering the seed covering to make it permeable to water
and gases.
1. Rubbing the seed on sand paper.
2. Cutting with a knife
3. Cracking the seed cover with a hammer
4. Scratching in pestle and mortar.

For large scale operation, special mechanical scarifiers are used. Here, seeds may be
tumbled in drums lined with sand paper or in concrete mixtures combined with coarse sand or
gravel. The sand and gravel should be of a different size than the seed to facilitate separation.
Eg. Leguminous seeds

37
 2) Acid scarification
Concentrated sulphuric acid is used to modify hard or impermeable seed covering.Dry seeds are
placed in glass or earther ware containers and treated with concentrated sulphuric acid in the ratio
of about one part of seed to two parts of acid. The mixture should be stirred in intervals to produce
uniform results.The length of treatment should be carefully standardized. This may vary from 10
minutes for some sp. to as much as 6 hours for other sp.At the end of treatment , the acid is poured
off and the seeds are washed with copious amount of water.

3) Soaking seeds in water

It is done to modify hard seed coat, remove inhibitors, soften seed coat and reduce the time of
germination. This will overcome seed coat dormancy and stimulate germination. The seeds can be
soaked either in cold or hot water depending on the species. Seeds of winged bean are very hard
and normally soaked in cold water for 48 hours so as to hasten the germination.
In hot water treatment, temperature of water will range from 77 oc to 100oc. After treating for one or
two minutes, the heat is immediately removed, and the seeds are allowed to soak in gradullay cooling
water for 12 to 24 hours. Following this, unswollen seeds can be separated from the swollen ones.

II. Stratification : (Moist chilling)

Here, seeds are exposed to low temperature. It permits physiological changes to occur in the embry.
Temperature range is from 0oc to 10oc. So dry seeds should be soaked in water for 12 to 24 hours,
drained, mixed with moisture retaining medium and then stored for the required period of time. The
usual storage temperature is 2oc to 7oc. For most of the seeds, low temperature stratification ranged
from 1 to 4 months. After it underwent the stipulated period, seeds are sown without drying.
III. Chemical stimulants
GA
It will promote germination in some kind of dormant seed. Seeds are treated with GA by soaking for
24 hour in water solution at concentration from 100 to 12000 ppm. This will improve seed
germination.

Cytokinin (Kinetin)
Commercial preparation of kinetin are available. A common synthetic cytokinin is Benzyl Adenine.
Seeds are soaked in 100 ppm kinetine solution for three minutes. First, the chemical is dissolved in
small amount of dil. Hel, then made up with water to get the required concentration.

Ethylene
When ethylene was applid to seeds, it stimulated germination of some seeds experimentally. In
peanut or groundnut (Virginia type), ethylene is used in the form of ethrel to break the dormancy.
Potassium nitrate
Freshly harvested dormant seeds germinate better after soaking in potassium nitrate solution.
Potassium nitrate solution of 0.2% concentration will improve seed germination in Kentucky
bluegrass.

Thio-urea
It is used to stimulate germination of some dormant seeds, particularly those that do not germinate
in darkness or at high temperature or that require a moist chilling treatment. Concentration varies
from 0.5 to 3%. Soaking is done for 24 hours.

Seed invigouration:
In most of the species, as the seed ages, it slowly looses the germination capacity due to a number
of factors like accumulation of inhibitors etc., These aged seeds when treated with specific chemicals
like potassium dihydrogen orthophosphate (KH2 PO4) sodium dihydrogen orthophosphate (NaH2
PO4), dipotassium hydrogen phosphate (K2HPO4) at a concentration of 200 ppm for 24 hours,
drying to original moisture and then sowing has improved the germination tremendously. In some
cases even water soaking has improved the germination eg. Papaya and chillies.

38
Lecture 14: Definition of division and Separation –Methods of division-Bulbs and Corms and Separation
Stem tuber, Tuberous root, Rhizome, Suckers, (shoot and root suckers) runner and Off sets- Example for
each type.

Many herbaceous species that die back at the end of the growing season have under ground food
storage organs that survive the dormant winter period. These organs are also vegetative
propagation structures that produce new shoots in the growing season. The variety of under
ground storage organs may be grouped into two classes based on how they are propagated; plants
propagated by separation and plants propagated by division.
Plants propagated by separation: Separation is a method of propagation in which underground
structures of plants are divided not by cutting but by breaking along natural lines between
segments. Separation is breaking away of daughter structures from the parent structure to be used
to establish new plants. Two specialized underground structures-bulbs and corms-produce such
materials.

Onion Bulb Seperation of bulblets

Bulb: A bulb is a specialized underground organ that consists predominantly of fleshy leaf
scales growing on a stem tissue (basal plate).The scales wrap around a growing

point or primordium to form a tight ball. Lateral bulblets, or miniature bulbs, originate in the
axils of some of these scales and when developed (offsets) may be separated from the
mother bulb to be planted independently as new plants.
There are two types of bulbs-Tunicate and non-tunicate bulbs.
Tunicate-These bulbs have outer bulb scales that are dry and membranous. This covering
called tunic, provide protection from drying and mechanical injury to the bulb. The fleshy
scales are in continuous, concentric layers, called lamina, so that the structure is more or
less solid. E.g. Onion, daffodil, tulip etc.
Non-tunicate (scaly) bulbs: These bulbs don‘t possess the enveloping dry covering. The
scales are separate and attached to the basal plate. The scales are not tight but loose and
can be removed individually from the bulb. In general, the non-tunicate bulbs are easily
damaged and must be handled more carefully than tunicate bulbs. The daughter bulbs or
bulb lets develop at the base of the of the scales of the mother bulb.Eg.Galdiolus, Lily etc.,

39
 Gladiolus corm
(Source: Plant facts Ohio state university)

Corm
Corm: The bulb consists predominantly of modified leaves; the corm is a modified stem. Food
is stored in this compact stem, which has nodes and very short internodes and is wrapped up
in dry, scaly leaves. When a corm sprouts into a new shoot, the old corm becomes exhausted
of its stored food and is destroyed as a new corm forms above it. Several small corms, or
cormels, arise at the base of the new corm. The cormels may be separated from the mother
corm at maturity (die back) and used to propagate new plants.Eg. Amorphophallus, Colocasia,
Gladiolus etc.

Plant propagation by division: It is a method of propagation of plants using cut section of a

particular part like rhizome, tuber and tuberous root etc.

Rhizome of Canna Rhizome division

Rhizome: A rhizome is a specialized stem structure in which the main axis of the plant grows
horizontally just below or on the surface of the ground. The stem appears segmented
because it composed of nodes and internodes. The rhizome appears as a many branched
clump made up of short individual sections. The rhizome tends to be oriented horizontally
with roots arising from the lower side.
In propagating plants by rhizome by cutting the rhizome into different sections being sure
that each section has at least one lateral bud or eye. It is essentially a stem cutting. Eg.
Bamboo, Banana, Iris etc.

40
 Stolon: It is a term used to describe various types of horizontally growing stems that
produce adventious roots when come in contact with the soil. These may be prostate or
sprawling stems growing above ground.

Stolon
In propagating plants by stolon, the stolon can be treated as a naturally occurring rooted layer
and can be cut from the parent plant and planted separately. Eg. Mint, Bermuda grass etc.

Runner of Strawberry

Runner: A runner is a specialized stem that develops from the axil of a leaf at the crown of
a plant, grows horizontally along the ground and forms a new plant at one of the nodes.
In propagating plants by runners, the rooted daughter plants are dug when they have
become well rooted and transplanted to the desired locations. Eg. Straw berry, oxalis, blue
berry etc.

Stem tuber of Potato

Stem tuber: A tuber is specialized swollen underground stem which possesses eyes in
regular order over the surface. The eyes represent the nodes of the tuber. The arrangement

41
of the nodes is spiral, beginning with the terminal bud on the stolon to produce a new plant,
the tuber is divided into sections so that each section has a good amount of stored food and
a bud or eye.
Propagation by tubers can be done either by planting the tubers whole or by cutting them
into section, each containing a bud or eye. Eg.Potato.

Root tuber of Sweet potato

Tuberous roots: These are thickened tuberous growth that functions as storage
organs. These differ from the true stem tuber, in that they lack nodes and internodes.
Buds are present only at the crown or stem end. Fibrous roots are commonly produced
towards the opposite end.
Most plants with fleshy roots must be propagated by dividing the crown so that each
section bears a shoot bud.Eg. Dahlia, Begonia, Sweet potato.

Offset of Pistia

Offset: It is a short thickened horizontal branch growing out of the crown ending at the apex
with a tuft of leaves and a cluster of leaves below. These are special type of branches or
lateral shoots which are produced from the base of main stem of parent plant.
The offset often breaks away from the mother plant and the daughter starts a new
independent life. Eg. Pistia, Agave, Water hyacinth, Cycas, Dracaena etc.

Suckers: It is a lateral branch developing from the underground parts of the stem or roots.
The suckers arise from below the surface of the soil. There are two types of suckers.

42
 Stem sucker of Mint
a) Shoot suckers: These will arise from the base of the stem. The suckers may grow
obliquely upwards and directly give raise a leaf shoot. Often it grows horizontally
outwards only to certain extent but soon turn up. It strikes roots when it is still attached
to the parent plant or when separated and planted. Propagation by shoot suckers can be
done by separating the suckers and planting. Eg.Chrysanthemum, Banana, Pineapple,
Yucca.

b) Root suckers: The root suckers will arise from the adventitious buds on the roots.

Propagation by shoot suckers can be done by separating the suckers and planting. Eg.Guava,
Millingtonia, Curry leaf,Quis quails etc.

43
Lecture 15: Plant Propagation Structures- Green house, Lath house, Hot bed, Cold
Frame, and other propagating frames.

Plant Propagation Structures

The structures which facilitate propagation of plants are called propagation structures. Propagation
structures are required for propagating plants by seed, cuttings and grafting. Propagation structures are of
two types; i) The first type a structure with temperature control and ample light, such as a green house,
modified quonset house, or hot bed – where seeds can be germinated or cuttings are rooted or tissues
culture micro-plants are rooted and acclimatized and the ii) The unit is structure into which the younger,
tender plants can be moved for hardening, preparatory to transplanting out-of-doors. Cold frames, low
polyethylene tunnels or sun tunnels covered by saran cloth and lath-houses are useful for this purpose.
1. Greenhouses
Greenhouse has been used long back by horticulturists as a mean of forcing rapid growth of plants and
extending the growing season particularly in colder areas. These are being used for whole sale production
and propagation of floricultural plants, nursery stock of fruit crops and vegetable crops.
A greenhouse greatly extends the variety and scope of propagation. These greenhouses may be plastic
polyethylene covered or made form fiberglass. Modern greenhouses are well equipped with elaborate
structures and have precise control on temperature, light intensity and humidity. The size and type of
greenhouses, primarily depends upon the need of the plant propagator.
On commercial scale several greenhouse units are often attached side-by-side for eliminating the cost of
conversing the adjoining walls with glass or polyethylene. The heating and cooling equipment is more
economical to install and operate, as large area can be shared by the same equipment.
2. Hot frames (Hot beds)
A hotbed is a bed of soil enclosed in a glass or plastic frame. It is heated by manure, electricity, steam, or
hot-water pipes. Hotbeds are used for forcing plants or for raising early seedlings. Seeds may be started
in a heated bed weeks or months before they can be sown out of doors. At the proper time the hotbeds
can be converted into a cold frame for hardening. Hot beds are small low structures, used for propagation
of nursery plants under controlled conditions. Hot beds can be used throughout the years, except in areas
with severe winters, where their use can be restricted to spring, summer and fall. Another form of a hot
bed is a heated, low polythene tunnels or sun tunnels that is made from hooped metal tubing or bent PVC
pipe, which is covered with polyethylene. For small propagation operations, hot beds structures are suitable
for producing many thousands of nursery plants, without the higher construction expenditure for larger,
propagation houses.
3. Cold frames
A cold frame is a bottomless box with a removable top. It is used to protect small plants from wind and low
temperatures. No artificial heat or manure is used inside a true cold frame. They utilize the sun's heat. The
soil inside the box is heated during the day and gives off its heat at night to keep the plants warm. The
frame may be banked with straw or manure to insulate it from the outside air and to retain heat. Cold
frames include not only low polyethylene-covered wood frames or unheated sun tunnels that people cannot
walk within, but also low-cost, poly-covered hoop houses. The covered frames should fit tightly in order to
retain heat and obtain high humidity. Cold frames should be placed in locations protected from wind. The
primary use of cold frames is in conditioning or hardening of rooted cuttings or young seedlings prior to
field, nursery row or container planting. Cold frames can be used for starting new plants in late spring.
Low-cost cold frame construction is the same as for hot beds, except that no provision is made for supplying
bottom heat.The installation of mist line or irrigation provision in cold frame is essential to maintain humid
conditions. During sunny days, high temperature condition can be controlled by providing ventilation and
shading.
4. Lath houses
Lath (lath – thin strip of wood) or shade houses provide outdoor shade and protect container-grown plants
from high summer temperature and high light irradiation. They reduce moisture stress and reduce the
moisture requirement of plants. Lath houses have many uses in propagation, particularly in conjunction
with the hardening off and acclimatization of liner plants prior to transplanting and for maintenance of
shade requiring plants. In mild climates, they are used for propagation, along with a mist facility and can

44
be used as overwintering structures for liner plants. However, snow load can cause problems in higher
latitude regions.
5. Propagation frames
Sometimes in a greenhouse, the humidity is not enough to allow satisfactory rooting in the leaf cuttings. In
such cases, enclosed frames covered with glass or plastic material may be used for rooting of cutting.
These frames are useful only on grafted plants as these retain high humidity during the process of healing.
Large inverted glass can also be kept over a container having cuttings. Though, high humidity is required
is such frames but ventilation and shading is necessary after the rooting process has started in the cutting.
Warm and humid conditions inside these structures provide excellent environment for growth of pathogenic
organisms, which may infect the propagation material. It is therefore, necessary to maintain cleanliness
and proper sanitation in such structures.
6. Net house
Net houses are widely used as propagation structures in tropical areas, where artificial heating is not
required and artificial cooling is expensive. In these areas, net houses may be constructed with roofs
covered with glass or plastic film and its sides are covered with wire net. It provides necessary ventilation
and maintains an ideal temperature for germination of seeds and subsequent growth of the seedlings. The
roof of net house may be covered with gunny cloth or even with live plant creeper to cut off the solar radiant
energy and to keep the house cool.
7. Bottom heat box
It is a simple box for promoting rooting of cutting in difficult-to-root fruit plants like mango and guava. It
consists of two chambers made from galvanized iron sheets. The outer chamber has a height of 70cm with
46cm width and the inner chamber has a height of 68cm and width of 44cm. The space between the two
chambers is filled with glass wool for heat insulation.
Another chamber is fitted inside the inner chamber with the height of 35cm fitted with two electric bulbs at
the bottom for providing heat to the cutting. The innermost chamber is filled with soil mixture or any other
propagation medium and the cuttings are inserted in it. Two electric bulbs of 100 watt capacity are fitted at
the bottom of the chamber to provide heat and light to the cuttings. Similarly, the temperature in the box is
maintained and controlled automatically by a thermostat fitted at the bottom of the chamber. The most ideal
temperature to be maintained in the box is 30± 20C because at this temperature, cuttings of mango, walnut,
olive and guava root easily and profusely. The initiation of rooting in cutting varies from species-to-species
but in general, it takes 1-2 months for proper development of the roots.
8. Mist propagation unit
The rooting of softwood leafy cutting under spray or mist is a technique now widely used by nurserymen
and other plant propagators throughout the world. The aim of misting is to maintain humidity by a
continuous film of water on the leaves, thus reducing transpiration and keeping the cutting turgid until
rooting take place. In this way, leafy cuttings can be fully exposed to light and air because humidity remains
high and prevents damage even from bright sunshine. Mist also prevents disease infection in the cuttings
by way of washing off fungus spores before they attack the tissues. While the leaves in this process must
be kept continuously moist, it is important that only minimum water should be used. This is because
excessive water leaches out nutrients from the compost, which may cause starvation. Moreover, a directly
injurious effect on the cutting may occur from over watering. Hence, it is necessary to utilize nozzles
capable of producing a very fine mist.
9. Growing rooms
A growing room is an insulated building from which natural light is usually excluded. In it, illumination is
provided by artificial means. Growing rooms are now widely used commercially for the production of
seedlings of bedding plants, tomatoes and cucumbers in most advanced countries. The seedlings are
usually grown in trays or pots kept on benches. To save space, the benches are usually installed in tiers
being vertically about 2 feet long and 6 inch wide. Each bench is illuminated with 8 feet long 125-watt
fluorescent tubes mounted 1 foot 6 inches above the bench. Seven tubes over each bench provide a light
intensity of 500 lumens per square feet, which is adequate for bedding plants.
10. The automatic greenhouse
Today, the modern green houses can be almost completely automated thus assisting propagation. For
instance, by the use of thermostats, air and bed temperature can be maintained as per the requirement.
Similarly, automatic ventilation allows the ventilators to open and close in relation to temperature. Even,
45
automatic systems of irrigation are installed in the modern greenhouses and water is supplied to the plants
through drip or trickle system to each pot or plant by individual nozzle of time switch.
11. Phytotron
Most advancement in raising of plants under highly controlled environmental conditions has been the use
of phytotron facility. National Phytotron Facility is available at Indian Agricultural Research Institute (IARI),
New Delhi.

Lecture 16: Propagation by Cuttings-Definition of Cutting-Different methods of Cuttings-Stem cuttings-

Hard wood cuttings, Semi hard wood, Soft wood and Herbaceous stem cuttings –example for each type.
Leaf cuttings.
Propagation by Cuttings:

The process of propagation of plants by cuttings is known as cuttage. A cutting is a part of a plant
that will produce roots when put in soil media and eventually produce a new plant quite true to the
parent plant.

A cutting may be a piece of stem, a leaf or part of a leaf, a piece of root, or root stock, or
even a scale of bulb.
Classification of cuttings:
Cuttings are usually classified in to 3 groups according to the particular part of the plant
used as cutting.
1) Stem cuttings
2) Root cuttings
3) Leaf cuttings

Stem cutting: Stem cuttings can be divided in to 4 types based on the degree of maturity
and lignification of wood used in making cuttings.
 Hard wood stem cuttings
 Semi hard wood stems cuttings
 Soft wood stem cuttings
 Herbaceous stem cuttings

Hard wood stem cuttings: These cuttings are made from the past seasons growth or wood
that has matured and lignified are known as hardwood cuttings.

46
Preparation and planting: Select a fully matured shoot with normal internodes from a
healthy, vigorous plant growing in full sun light. Remove all the leaves with
outdamaging the axillary buds. Give a slant cut just below the basal node of the selected
shoot. Measure the required length (about 15 to 25cm and containing 3 to 4 buds) from the
base of the shoot and give a horizontal cut 1 to 2.5cm above the top node. Repeat the
procedure and prepare as many cuttings as possible from the shoot. In case of difficult to
root species treat the prepared cuttings with recommended growth regulators to induce
rooting. Make holes in the prepared bed or pot with the help of a stick or dibbler. Insert the
cuttings in the hole such that at least two nodes are inside the soil. Take care of polarity while
planting cuttings. After planting press the medium firmly around the cutting and water
immediately. Eg: Grape, Fig, Pomegranate, Bougainvillea, Acalypha,Rose etc.

Hard wood cuttings may be of three types: Straight or simple cutting, heel cutting
and mallet cutting.
Types of Hard wood cuttings

Mallet Heel Straight

Types of hard wood cutting

Straight or simple cutting: It consists of only the current year‘s wood and doesn‘t
bear any older wood.Eg. Hibiscus, nerium.

Heel cutting: A small piece of older wood is retained at the base of each cutting Eg.
Rose
Mallet cutting: An entire section of the older wood is retained.Eg.Thuja.

Semi-hard wood stem cuttings: Semi hard wood cuttings are prepared from new shoots
just after a flush of growth which is partially matured.

Preparation and planting: Select partially matured shoots from a healthy and vigorous
growing plant and take out the terminal 7 to 15cm portion by giving a horizontal cut just below
a basal node. Remove all the leaves towards the base of the shoot and retain only the
terminal leaves. If the retained leaves are very large, reduce their size by cutting the top half
portion. This facilitates planting the cuttings closer and also minimizes the loss of water from
cutting. Plant the cuttings in the same way as hard wood cuttings are planted .Eg.
Camellia,Citrus,Eranthemum,Acalypha,Geranium, Hibiscus, Jasmine, Lemon, olive etc.

47
 Soft wood cuttings: Cuttings are prepared from the soft succulent new spring growth of
species which are 4 to 6 months old.
Preparation and planting: Select the soft succulent shoots from a healthy and vigorous
growing plant, growing in full sun light and take out the terminal 7 to 15cm portion by giving
a horizontal cut just below a basal node. Don‘t remove the leaves except for the part to be
buried inside the rooting media. Soft wood cuttings should be kept in green house or in moist
chamber where a high humidity can be maintained which keeps the tissues in turgid
condition.Plant the cuttings in the same way as hard wood cuttings are planted.Eg. Nerium,
crotons, Eranthemum, Graftophyllum etc.

Herbaceous stem cuttings: This type of cuttings is taken from succulent herbaceous green
house plants.

Preparation and planting: Select the succulent herbaceous shoots from a healthy and
vigorous green house growing plant. Retain all the leaves. Give a basal cut below a basal
node. Plant the cuttings in the same way as hard wood cuttings are planted. Eg.
Chrysanthemum, Coleus, Carnations, Geraniums, Cactus etc.
Leaf Cuttings: Certain plants with thick and fleshy leaves have the capacity to produce
plantlets on their leaves. In leaf cuttings, the leaf blade with or without petiole and axillary
bud is used for starting new plants. Adventious roots and shoots form at the base of the leaf
and form in to a new plant. However, the original leaf does not become a part of the new
plant.
Frequent watering and high humidity and bottom heating are desirable for better and rapid
rooting of leaf cuttings. Sand or sand and peat moss (1:1) are satisfactory rooting media for
leaf cuttings.
For leaf cuttings, depending on the species the whole leaf blade, leaf blade sections or the
leaf with petiole is used. So, leaf cuttings can be classified in to:
1. Leaf blade cutting
2. Leaf vein cutting / Leaf slashing
3. Leaf margin cutting
4. Leaf bud cutting

Leaf Section cutting-- Sansevieria.

48
Leaf blade/Leaf section cutting:
Preparation and planting: Select a healthy leaf and Give a slanting cut towards the base
of the leaf. Measure a length of about 7 to 10-cm and give a horizontal cut towards the
terminal end. Prepare as many cuttings as possible from the selected leaf. Insert up to ¾ of
the prepared leaf cuttings in to the medium. Take care of polarity while planting the cuttings.
Compress the soil around the leaf cuttings and water immediately.Eg. Sansevieria.

Leaf vein cutting/Leaf slashing:

Preparation and planting: Select a healthy and full mature leaf and detach it from the
mother plant. Give cuts to alternate veins closer to the petiole on the lower surface of the
leaf. Keep the leaf flat on the medium in such a way that the lower portion comes in contact
with the medium. Pin or hold down the leaf in some manner so as to expose the upper
surface and to maintain the contact between the cuts on the vein and the rooting medium.
Water the cuttings carefully Eg. Begonia rex.

Leaf vein Cutting

Leaf bud cuttings: This cutting consists of a leaf blade, petiole and a short piece of the stem
with attached axillary bud. This is practiced in species that are able to initiate roots but not
shoots from the detached leaves. In such case the axillary bud at the base of the petiole
provides for the essential shoot formation.

Leaf bud cutting

Preparation and planting: Select a healthy and mature shoot with well developed buds
and healthy active growing leaves. Separate each leaf along with the axillary bud

49
and a small portion of the stem. Repeat the process until possible number of leaf bud cuttings
are made.Treat if necessary the cut surface of the prepared cuttings with the recommended
root promoting substance to stimulate rapid root formation. Insert the prepared cutting in the
rooting medium so that the bud is1.5 to 2.5 cm below the surface. Compress the medium
around the cutting and water immediately. Eg. Black berry, Camellia, Lemon ,Rhododendron
and raspberry etc.

Leaf Margin Cutting of Bryophyllum

Leaf margin cutting:
Preparation and planting: Select a mature and healthy leaf with the foliar embryos intact.
Keep the leaf flat on the rooting medium. If the leaf is folded, just cut along the mid rib, so
that the leaf can be kept flat on the medium. Keep some weight on the leaf or partially cover
it with soil, so that the margin comes in contact with the medium. Water the cuttings carefully
Eg. Bryophyllum.

Root cuttings: Plants which give rise root suckers freely are propagated by root cuttings.

Root cuttings

50
Lecture 17: Plant propagation by layering-Definition of Layering and Layer-Types of Layering- Tip
layering, Simple layering, Trench layering, mound or Stool layering, Compound or Serpentine layering
-Air layering, Examples for each layering.

Plant propagation by Layering

Layering is the developing of roots on a stem while it is still attached to the parent plant. The
rooted stem is then detached or become a new plant growing on its own roots. A layered stem is
known as a layer.

Layering includes several forms of ground and aerial layering. When rooting is encouraged on the
aerial part of a part of a plant after wounding it is known as air layering or gooty or marcottage.
When branches running parallel to ground are utilized, it is known as ground layering, The root
formation during layering on a stem is stimulated by various stem treatments like ringing, notching
etc, which causes an interruption in the downward translocation of carbohydrates and other growth
factors from leaves and growing shoot tips.
However, the root formation in layered stems, completely depends upon continuous moisture
supply, good aeration and moderate temperature around the rooting zone. Some times synthetic
growth regulators like IBA, IAA etc, are also treated to layered stem to induce better rooting, as
the auxins in layered stem is an important factor for rooting.
Advantages:
i. It is an easy method and does not require much care and
arrangement like cutting.
ii. The mother plant supplies nutrient and other metabolites as it
remains attached while rooting.
iii. By using a large branch a much larger plant can be obtained in the
first instance.
iv. Some plants that cannot be satisfactorily started from cuttings can be
propagated by layering.
Dis advantages:
i. It is a costlier method.
ii. It is a slow process
iii. Limited number of plants can be propagated
iv. Layered plants are generally shallow rooted
v. Interference with cultivation
51
 vi. Require more individual attention
vii. The beneficial effect of root stock cannot be exploited.

Classification of layering:
I. Ground layering
1) Tip layering
2) Simple layering
3) Trench layering
4) Mound layering or stool layering
5) Compound or serpentine layering
II. Air layering. (Gootee or Marcottage).

Tip layering
Tip layering: It is generally followed in plants which have trailing type of shoots. It is quite similar
to simple layering.
Procedure: Dig a hole 3 to 4 inches deep. Insert the tip of a current season‘s shoot and cover it
with soil. The tip grows downward first, then bends sharply and grows upward. Roots form at the
bend. The re-curved tip becomes a new plant. Remove the tip layer and plant it in late fall or early
spring. Examples of plants propagated by tip layering include purple and black raspberries, and
trailing blackberries

Simple layering
Simple Layering: In this method, a branch is bent to the ground and some portion of it is covered
by soil leaving the terminal end of the branch exposed.Root initiation takes place at the bent
and buried portion. After allowing sufficient time for root formation, the rooted stem is separated
from the mother plant. Eg. Bougainvillea, Jasmine, Rangoon creeper.

52
Procedure: Select a healthy, flexible and sufficiently long (50 to 60cm) branch towards the base
of the plant. The selected branch should be closer to the ground. At a distance of about 15 to
30cm back from the tip give a sharp, slanting inward and upward cut 1.5 to 2.5cm below a node
and insert a small wood splinter. Bend the shoot gently to the ground so that the treated part can
conveniently be inserted into the soil. Cover the treated region with soil. Peg down the shoot or
keep a stone of brick on the covered soil to keep the layered shoot in place. Drive a vertical stake
into the soil by the side of the layered branch and tie the terminal portion of the branch to keep it
upright. Water the layered portion regularly so as to keep it moist all through till root initiation take
place. After sufficient root formation separate the layer by cutting just below the rooted zone.

Compound or serpentine Layering: Compound layering is essentially the same as the simple

layering except that the branch is alternatively covered and exposed along its length. The branch
for compound layering must be long and flexible so that it can be layered at different places along
its length. Eg. Bougainvillea, Jasmine, Rangoon creeper.
Procedure: Select a healthy, flexible and sufficiently long (100 to 250 cm) basal branch that is
close to the ground. Give a sharp slanting, inward and upward cut 1.5 to 2.5 cm below a node at
30cm interval starting from the tip leaving 3 to 3 buds in between two such cuts. Bend the shoot
gently to the ground, and insert and cover the cut portions with the soil exposing the uncut portions.
The remaining steps are same as in simple layering.

Mound or stool layering

Mound (stool) Layering: In this method, a plant is cut back to the ground level during the dormant
season and soil is heaped around the base of the newly developing shoots. After slowing sufficient
time for root initiation, individual rooted layers are separated from the mother plant and panted.
Eg. Apple roots tocks, Guava, Litchi, Quince,
Procedure: Select the plant to be mound layered or plant a rooted layer in a trench and allow it
to grow for a year. Cut back the plant to 2.5 cm from the ground level just before growth begins.
53
Allow the new shoots to develop. When these shoots have grown 7 to 15 cm tall, girdle them at
the base and treat the girdle portion with the recommended growth regulator and draw up the
loose soil round each shoot to half its height. When these shoots have are 20 to 25 cm tall add
soil again to half their height. Add soil again when the shoots grow to a height of about 35 to 45
cm. Water the heaped soil regularly and allow sufficient time for the initiation of roots. A depression
can be made in the centre of the heap to hold water. After sufficient root formation, remove the
heaped soil and cut the rooted shoots individually to their base. Transplant the rooted shots in
pots or suitable containers.

Trench Layering
Trench Layering: Trench layering consists of growing a plant or a branch of a plant in a horizontal
position in the base of a trench and filling in soil around the new shoots as they develop, so that
the shoot bases are etiolated. Roots develop from the base of these new shoots. Etiolated roots
develop from the base of these new shoots. Trench layering is used primarily for woody species
difficult to propagate by mound layering. Trench layering is used primarily for woody species
difficult to propagate by mound layering. Eg. Apple rootstocks, Litchi, Quince.
Procedure: Dig small trenches of about 25-30cm deep and in about 1 m wide rows. Plant rooted
layers or one year old nursery – budded or grafted plants in the trenches in rows at an angle of
30O to 45 Oand 50 to 10cm apart within the row. The rows should be1.2 to 1.5 m apart. Just before
growth begins, lay the plant or a branch flat on the bottom of the trench. Plants must be kept
completely flat with wooden pegs or wire fasteners. Cut back the shoots slightly and remove the
weak branches. Add roots medium (sand or sawdust or peat moss) or their mixture at intervals to
produce etiolating on 5 to 10 cm of the base of the developing shoots. Apply first 2.5 to 5cm layer
before buds swell and repeat as shoots emerge and expand. At the end of the season, remove
the medium and cut off the rooted shoots close to the parent plant. Transplant the rooted shoots
in pots or suitable containers.
Air Layering
II. Air Layering: In air layering roots form on an aerial shoot. The rooting medium is tied to the
shoot for getting root initiation. Sphagnum moss is the best rooting medium for air layering as it
holds large quantities of water till root initiation and through the root initiation and through the root
development. Eg. Crotons, ficus, fig, Guava, Phalsa, Pomegranate.
Procedure: Select a healthy branch of previous season‘s growth. At a point 15 to 30 cm back
from the tip of the shoot make a girdle just below a node by completely removing a strip of bark 2
to 3.5 cm wide all around the shot. Scrape the exposed surface lightly to remove traces a phloem
or cambium to retard healing. In difficult-to- root species treat the girdled portion with the
recommended growth regulator to induce better rooting. Cover the girdled portion with moist
propagating medium. Sphagnum mass, saw dust, vermiculite. Tie the medium around the girdled
portion using a polyethylene sheet. Tying should be perfect so that no water can enter the treated
54
part. After observing the fully developed roots through the transparent polyethylene sheet,
separate the root zone and transplant the layer appropriately.

Stages of preparing an Air layer- piece of bark removed, scraping the exposed wood,
wrapping with moist rooting medium, tying, separating the branch from the mother plant,
separated air layer, planted air layer

Lecture 18: Plant Propagation by Grafting-Definition of Grafting-Methods of Grafting- Attached scion

method of Grafting, Simple or Approach grafting.

Plant propagation by grafting--Grafting is an art of joining parts of two independent plants in

such a manner that they unite and grow together into single independent plant. The part of graft
combination which is to become the upper portion or the shoot system or top of the new plant is
termed the scion or cion and the part which is to become the lower portion or the root system is
the rootstock or under stock or some time stock. The single plant obtained as a result of union
between the stock and scion is termed as Stion.

55
Methods of grafting: Mainly in grafting there are two types. Attached scion methods
of grafting and detached scion methods of grafting.

In attached scion methods of grafting the scion is still attached to the mother plant (Scion
Plant) till the graft union takes place where as in detached scion methods of grafting the scion
is separated from the scion plant or mother plant just before grafting.
Under attached scion methods of grafting simple inarching or approach grafting is most important.

Simple inarching
Simple inarching / Approach grafting: The distinguishing feature of this method of grafting is
that two independent plants on their own roots (self sustaining) are grafted together. This method
provides a means of establishing a successful union between certain plants which are difficult to
graft by any other method as the two plants will be on their own roots till the formation of successful
graft. Eg.Guava, mango, Sapota.
Procedure: Select a healthy shoot of having a 3.5cm girth on the selected mother plant which is
to be used as a scion source. Select a root stock (raised in pot) having approximately the same
size as that of the selected shoot on the mother plant. On the internodal region, where the union
is to occur, a slice of bark and wood 2.5 to5 cm long is cut from both the selected stock and scion
shoots. The cut should be given on the stock and scion should be of the same size. The cuts
should be perfectly smooth so that a close contact of the cambial layers of stock and scion is
brought about when they are pressed together. Tie the two cut surfaces together tightly with string
or cloth.

Lecture 19: Detached methods of Grafting-Veneer grafting, Side Grafting, Epicotyl grafting, Soft
wood grafting, Double working, Top working.

Pre-curing of scion: In detached scion methods of grafting, the scion is to be procured before
grafting. For precuring, a partially matured scion shoot about the thickness of a little finger is
selected. The maturity is indicated by the presence of dark green leaves and grey dark colour on
the shoots. The selected shoot is defoliated retaining only the petioles up to a length of about 4‖
from the apical bud. The defoliated shoot is left on the tree for a period of 7-10 days. During this
time, the bud on the shoot begins to swell. This shoot is then called as Pre-cured scion, which is
separated from the tree.

In detached scion methods of grafting there are two types-they are side grafting and apical
grafting methods.
Among the detached scion methods of grafting the important ones are described below.
56
Under side grafting method Veneer grafting is important and is described below.

A-Prepared root stock, B-prepared Scion, C-Scion inserted,D-Girdled stock and tied
graft joint,E-Sucessful graft,the stock being removed
Veneer grafting: This is also a kind of side grafting with slight modification .It is used widely for
grafting small potted plants and insitu grafting .Eg. .Avocado, Mango etc.
Procedure: On the stock plant, at the desired height, in the internodal region, give a shallow
inward cut running to a length of about 2.5 to 5cm. At the base of the first cut make another short
and inward cut intersecting the first cut and remove a piece of wood and bark. On the scion ,
towards the base, give a long (2.5-5.0cm), slanting cut towards one side and another short, inward
and downward cut on the opposite side. The cuts given on stock and scion should be of same
dimensions, so that, the cambium layers can be matched as closely as possible. Insert the scion
on to the rootstock such that a contact of cambium is established at least on one side, and tie
them firmly. After the union has healed, cut back the stock above the graft union either on gradual
steps or all at once.

Among apical detached scion methods of grafting the important ones are described below.

Epicotyl grafting
Epicotyl (Stone) Grafting: This method of grafting is done on the epicotyl region of the young
seedlings; hence the name epicotyl grafting. Eg. Cashew, mango etc.
Procedure: Select very young seedling about 10 days old raised in polythene bags of size
(15cmX22cm). Cut off the top portion of the chosen seedling leaving 5-6cm long shoot (epicotyl).
With a sharp knife make a vertical, downward slit (2-3cm long) at the centre of the remaining
portion of the epicotyl. Select a dormant 3-4 months old terminal shoot of about 5-8cm long
from a proven mother plant as the scion stick. Cut the lower end of the selected scion to a wedge
shape by giving slanting and inward cuts of 2-3cm on opposite sides. Insert the wedge shaped

57
scion in the slit made on the seedling and secure firmly with polythene strips or tape. Water the
graft regularly without wetting the graft region. In about three weeks the scion starts sprouting.
If the seedlings are raised in sand beds they are uprooted (with stones) 15 to 20 days after sowing
(when seedlings attain10-15cm height) and grafting is done as described above. The grafted
seedling is then planted in polythene bags or pots keeping the graft union above the soil level
and without damaging the stone. June to September is the best period for epicotyl grafting.

Soft wood grafting: It has been developed to graft small and young rootstocks which are grown
in situ or in pots. Eg. Cashew, Mango.

Procedure: Raise the rootstock seedlings in suitable containers or preferably in the main field
itself where the grafts are desired to be grown and allow them to grow for a year or more. When
the seedling attain a height of 30-45cm and the new shoot and leaves usually have bronze colour.
Decapitate the top portion of the fresh growth on the stock plant with a knife, retaining bout 8 cm
of the fresh stem. Make a longitudinal cut of 3 cm in the retained fresh stem. Select a scion stick
of about 10cm long and about the same thickness as of the prepared stem on the stock. Cut the
basal end of the scion to a wedge shape of about 3cm long by chopping the bark and a little wood
on two opposite sides. Insert the prepared wedge part of the scion stick into the slit made on the
stock and secure firmly with polythene strips. Water the grafted plant regularly. The scion sprouts
in about three weeks.
Double working: It is practiced for several purposes (1) to over come incompatibility between the
stock and scion.Iincompatible stock and scion may be united by means of a piece of interstock
that is compatible to both (2) to secure resistance to drought or cold by providing a disease or cold
resistant trunk by means of double working.(3) To obtain resistance to pest and dwarfing effect by
using a pest resistant stock and a dwarfing stock and (4) top working of grafted orchard trees is
essentially a double working; here the tree trunk as an intermediate stock may exert certain
influences on the new top.
The inserted intermediate stem piece is called as sinking scion / foster mother /interstock
/ inter stem.
Top working: Top-working for changing a variety is generally done on long lived species, growing
in a healthy condition. Short lived species, old trees or diseased trees are not suitable for top
working; in such cases new planting is considered more economical and useful than top working.

58
 Top working by cleft grafting

Top working by cleft grafting on main branches

This practice is resorted to (1) when the existing tree is of inferior type, (2) when the tree is
unproductive and (3) to provide pollenizers (4) to change the variety.

For top working different methods of grafting like cleft grafting, bark grafting, splice grafting or side
grafting can be used. However, cleft is the most popular and commonly used method for top
working especially when thick branches are selected.When younger and thin branches are used,
whip and tongue grafting are best.

Top working of older trees is generally done over a period of two years. In the first year, half of the
scaffold branches are top worked retaining the other branches as nurse branches which in turn
are grafted in the second year. In the smaller and comparatively younger trees the entire tree is
top worked in the first year. Here also one or more nurse branches are retained till the union is
successful. Nurse branches protect the top worked scions from winter injury, sun burn and also
from desiccating winds and water sprouts develop less frequently when nurse branches are
retained.
Top working is most successful when relatively young trees are used. If older trees are selected
for top working, it is better to select vigorous lateral branches that arise from the main limbs.
The branches to be top worked should be cut in such a way that the cut surface is smooth and is
at a point of the branch where there are no knots or smaller branches. Immediately after top
working the limbs should be thoroughly covered with grafting wax, sealing all the exposed cut
surfaces.

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Lecture 20: Stock-scion relationship – effect of rootstock on scion, effect of scion on rootstock; Graft
incompatibility - types of graft incompatibility.

Stock-scion relationship:
A grafted or budded plant can produce unusual growth patterns which may be different from what
would have occurred if each component part of a graftage viz., rootstock and scion was grown
separately or when it is grafted or budded in other types of rootstocks. Some of these have major
horticultural value. this varying aspect of rootstocks in the performance of a scion cultivar or vice
versa is known as stock-scion relationship
A. Effect of rootstock on scion cultivars:

1. Size and growth habit: In apple, rootstocks, can be classified as dwarf, semi- dwarf, vigorous
and very vigorous rootstocks based on their effect on a scion cultivar. If a scion is grafted on dwarf
rootstocks eg. Malling IX, the scion grows less vigorously and remain dwarf only. On the other hand
if the same scion is grafted on a very vigorous rootstock eg. Malling II the scion grows very
vigorously,. In citrus, trifoliate orange is considered to be the most dwarfing rootstock for grapefruit
and sweet oranges. On the other hand, in mango, all plants of a given variety are known to have the
same characteristic canopy shape of the variety despite the rootstocks being of seedling origin.
But recently, rootstocks of Kalapade, Olour have been found to impart dwarfness in the scion
cultivars of mango. Guava cultivars grafted on Psidium pumilum are found to be dwarf in stature.
2. Precocity in flowering and fruiting : The time taken from planting to fruiting i.e., precocity is
influenced by rootstocks. Generally fruiting precocity is associated with dwarfing rootstocks and
slowness to start rootstocks are precocious than those grafted on sweet orange or sour orange or
acid lime rootstocks
3. Fruit set and yield: Acid limes budded on rough lemon register nearly 70 percent increased yield
than those budded on troyer citrange, Rangpur lime or its own rootstock. Sweet orange var.
Sathugudi budded on Kichili rootstock gave higher yield that on Jambhari or on its own seedling.
4. Fruit size quality: Sathugudi sweet oranges grafted on Gajanimma rootstocks produced large
but poor quality fruits while on its own roots they produced fruits with high juice content and quality.
The physiological disorder ‘granulation’ in sweet orange is very low if grafted on Cleopartra mandarin
seedlings, on the other hand rough lemon seedlings stocks induced maximum granulation.
5. Nutrient status of scion: Roost stocks do influence the nutrient status of scion also. Sathugudi
orange trees have a better nutrient status of all nutrients in the leaves when it is budded on
C.volkarimariana rootstock than on its own rootstock or Cleopatra mandarin stocks
6. Winter hardiness: Young grape fruit trees on Rangpur lime withstand winter injury better than on
rough lemon or sour orange. Sweet oranges and mandarins on trifoliate stocks were more cold
hardy.
7. Disease resistance: In citrus considerable variability exists among the rootstocks in their
response to diseases and nematodes. For instance, rough lemon rootstock is tolerant to tristesa,
xyloporosis and execortis but is susceptible to gummosis and nematode. On the other hand, treyer
citrange is tolerant to gummosis but susceptible to execortis virus disease. Similarly, guava varieties
grafted on Chinese guava (Psidium friedrichsthalianum) resist wilt diseases and nematodes
8. Ability to resist soil adverse conditions: Among the citrus rootstocks, trifoliate orange exhibits
poor ability, while sweet oranges, sour orange, Rangpur lime rootstocks exhibit moderate ability to
resist excess salts in the soil. Im pome fruits, similarly, ariation exists among rootstocks to resist
excess soil moisture or excess boron in the myrobolan plum rootstocks generally tolerate excess
boron and moisture than Mananna plum root or other rootstocks viz., peach, apricot or almond.

B. Effect of scion on rootstock:

1. Vigous of the rootstocks: In apple, it has been found that if apple seedlings were budded with
the ‘Red Astrochan’ apple. The rootstock produced a very fibrous root system with few tap roots. On
the other hand, if scion ‘Golden burg’ was budded on the seedlings, they produced two or three
pronged deep roots without fibrous root system. In citrus, if the scion cultivar is less vigorous than
the rootstock cultivar the rate of growth and the ultimate size of the tree is more determined by the
scion rather than the rootstocks.

60
2. Cold hardiness of the rootstock: Cold hardiness of citrus roots is affected by the scion cultivar.
Sour orange seedlings budded to ‘Eureka’ lemon suffered much more from winter injury than the
unbudded seedlings.
3. Precocity in flowering: Yound mango rootstock seedlings (6 months to one year old) were found to
putforth inflorescence when the branches from old trees are inarched which can be attributed to the
influence of scion on the rootstock.

Types of incompatibility:
Graft incompatibility in fruit trees has been classified in to two types.

1. Translocated incompatibility.

2. Localized incompatibility

1. Translocated incompatibility: This type involves phloem degeneration and this can be seen
by the development of brown line or necrotic area in the bark. This is due to the movement of toxic
materials through the phloem. This cannot be overcome even by inserting an intermediate stock.

2. Localized incompatibility: Incompatibility reactions are seen at the graft joint. This
incompatibility can be overcome by inserting a mutually compatible interstock in between them by
avoiding direct contact between stock and scion. This may be due to repulsive action of stock
and scion.

Symptoms of incompatibility:

Graft union malformation resulting from incompatibility usually expresses the following external
symptoms viz.,
1. Failure to form a successful graft or bud union with a high percentage of success
2. Yellowing of leaves in the latter part of the growing season followed by early defoliation
accompanied by decline in vegetative growth, appearance of shoot die back and general ill health
of the tree.
3. Premature death of the trees which may live only a year or two in the nursery
4. Marked differences in the growth rate or vigor of scion and stock
5. Over growth at, above or below the graft union.

A B C
Graft incompatibility

A- At the joint B- Below the joint C- Above the graft Joint

61
Lecture 21: Plant propagation by Budding-Definition of Budding-Methods of Budding-T- budding and
Inverted T budding, Patch budding, Ring budding.

Budding is also a method of grafting wherein only one bud with a piece of bark and with or without
wood is used as the scion material. It is also called as bud grafting. The plant that grows after
union of the stock and bud is known as budding.

Methods of budding:

Shield budding / T- budding

T-Budding (Shield budding): This method is known as T-budding as the cuts given on the stock
are of the shape of the letter T, and shield budding as the bud piece like a shield. This method is
widely used for propagating fruit trees and many ornamental plants. This method is generally
limited to the stock that is about 0.75 to 2.50cm in diameter and actively growing so that the bark
separate readily from the wood. Eg.Citrus, Rose etc.

Procedure: After selecting the stock plant, select an internodal region with smooth bark preferably
at a height of 15-25 cm from ground level. Give a vertical cut through the bark to a length of about
2.5-3.75cm. At the top of this vertical cut, give another horizontal cut (1cm or 1/3 rd of the
circumference of the stem) in such a way that the two cuts given resemble the letter T. Lift the
bark piece on either side of the vertical cut for the insertion of the bud. Select a required bud stick
and start a slicing cut about 1.5cm below the bud and continue it upward and under the bud to
about 2.5cm above the bud. Give another horizontal cut about 1cm above the bud. Remove the
shield of bark containing bud. The traces of wood, if attached may be removed. Insert the bud
between the flaps of bark on the stock with the help of budding knife in such a way that the
horizontal cut of the shield matches the horizontal cut on the stock. Wrap the bud stick tightly with
polythene strip exposing only the bud.

62
Successful T budding requires that the scion material have fully-formed, mature, dormant buds
and that the rootstock be in a condition of active growth such that the "bark is slipping". This means
that the vascular cambium is actively growing, and the bark can be peeled easily from the stock
piece with little damage.

Inverted T- Budding: In heavy rainfall areas, water running down the stem of the stock may enter
the T cut, soak under the bark and prevent healing of the bud piece. Under such conditions an
inverted T ( ) budding may give better results as it is more likely to shed excess water. Inverted T
budding procedure is same as that of T- budding except the horizontal cut on the stock is made
at the bottom of the vertical cut rather than at the top.
Procedure: On the selected stock plant, give a horizontal cut at the bottom of the given vertical
cut representing inverted T. Select the required bud stick. Start a slicing cut 1.5 cm above the bud
and continue it downward and under the bud to about 2.5 cm below the bud. Give another
horizontal cut about 1cm below the bud and remove the bud piece. Insert the bud between the
flaps of bark on the stock and push upwards till the horizontal cut of the shield matches the
horizontal cut on the stock. Wrap the bud piece and stock completely and tightly exposing only
the bud properly.

Patch Budding: In this method a regular patch of bark is completely removed from the stock
plant and is replaced with a patch of bark of the same size containing a bud from the desired
mother plant. For this method to be successful, the bark of the stock and bud stick should be easily
slipping .The diameter of the stock and bud stick should be preferably by about the same (1.5 to
2.75cm) E.g., Ber, Citrus, Cocoa and rubber.

Patch Budding

Procedure: On the selected stock plant at the desired place (10-15cm above the ground level)
give two transverse parallel cuts through the bark and about 1-1.5 cm long or 1/3rd the distance
around the stock. The distance between the cuts may be 2-3 cm. Join the two transverse cuts at
their ends by two vertical cuts. Remove the patch of bark and keep it in place again until the bark
patch with the bud from the selected mother plant is ready. On the bud stick give two transverse
cuts-one above and one below the bud-and two vertical cuts on each side of the bud. The
dimensions of the transverse and vertical should correspond to those given on the stock. Remove
the bark patch with bud by sliding side ways. Cuts with bud by sliding side ways. Insert the bud
patch immediately on the stock in such a way that the horizontal cuts of the bark patch and those
63
on the stock plant match together perfectly. Wrap the inserted bud patch with polythene strip
covering all the cut surfaces but exposing the bud properly.

Ring budding
Ring budding: The bud is prepared by taking a ring of a bark, 3cm long with the bud in the centre.
In the root stock, two transverse cut 1.5cm apart are made and these are connected with a vertical
cut and a ring of bark is removed. The prepared scion bud with the ring of bark is fitted in the
exposed portion of the rootstock and tied.E.g, Cinchona.

Lecture 22: Training- Definition –Objectives of Training fruit trees-Methods of Training- Central
leader, Open centre and Modified Leader system with merits and demerits.
Training refers to the judicious removal of plant part / parts to develop proper shape of a plant
capable of bearing a heavy crop load whereas pruning is defined as the judicious removal of plant
parts like root, leaf, flower, fruit etc.to obtain a good and qualitative yield.

Thus, it can be conceived that the training is related to shape and size of plants where as
pruning is related with harvesting better yield and more so harvesting fruits of quality.

Both the operations of training and pruning work together in maintaining shape and size of tree
and harvesting desirable yield.

Training is a treatment given to the young plants to get a suitable or desirable shape with strong
framework. It may or may not involve pruning.

Pruning is the removal of unwanted, surplus annual growth; dead, dried and diseased wood of
the plants is called Pruning.
Before actually discussing the subject of training, it is necessary to understand the various terms
used to make the subject more intelligible.

Trunk: The main stem of the plant.

Head: The point on the trunk from which first branches arise.

Scaffold branches: The main branches arising from the head are known as scaffold branches.
Trees in which scaffold branches arise with in 60-70cm height from the ground level are called
low head trees and those in which they come out from the trunk above 120cm are called high
head trees.

Crotch: The angle made by the scaffold limb to the trunk or the secondary branch to the scaffold
limb is called crotch.

Leader: The main stem growing from ground level up to the tip dominating all other branches is
64
called leader.

Water shoot: A vigorous growing unbranched shoot arising on any branch or leader is
called water shoot.

Water sucker: The growth appearing on rootstock portion is called water sucker. The reasons

for training fruit trees, ornamental trees, shrubs etc. are:

1) There are no. of plants, which grow wild and don‘t bear if they are left to
themselves and will not have any symmetry in their growth.
2) Most of the time, the unpruned trees put forth vegetative growth only. Hence,
bearing will be delayed.
3) When plants are grown in rows at close spacing, they grow tall and occupy
interspaces, making intercultural operations difficult to practice.
4) For want of sunlight, the lower branches wither and die. The shaded fruits
(apple, citrus etc.) fail to develop colour.
5) Untrained trees will generally be less productive because of excessive
vegetative growth for most of the time.
6) The framework being weak in untrained trees, it breaks easily due to strong
winds as well as heavy loads of crop.
All the above problems can be overcome by training the trees. Man can train the plant to suit his
desire. By training the plants, ideal conditions a can be provided for better production.

The fruit trees are trained to a particular system depending upon their habit of growth and the
flowering and ornamental shrubs etc. can be trained to a particular shape like animals, birds etc.

It is necessary to pay attention to the training of a plant during the first few years when it is young.
In this period, its permanent framework is built up as decided upon by the grower.

The main objectives to be kept in view in training the fruit trees are:

 To facilitate orchard cultural operations.

 To provide an attractive appearance.
 To admit more light and air to the centre of the tree and to expose maximum
leaf surface to the sun
 for increasing production
 for complete colour development
 To protect the tree trunk from sunburn injury.
 To secure a balanced distribution of fruit bearing parts on the main limbs of the
plant.
Most deciduous and evergreen woody trees are best trained to a single stem with a low head.
In case of pomegranate, custard apple and fig it would be better to train two or three stem plant
and remove the other stems that may grow later.

65
In the tropical climate, the high-headed trees are unsuitable as their exposed trunks are subject
to sunscald in summer. Low headed trees are common all over the world. In such trees the heads
or crown is kept so low on the trunk that there is only a distance of 60-- 90cm (2—3 ft.) between
the ground and the lowest branch. Such low headed trees come in to bearing comparatively much
earlier, are able to resist stormy winds more effectively and their spraying and harvesting also
become easy.

The formation of the main frame work of the tree is the most important part of the training.

1) Usually, two to four main branches are encouraged. These should be allowed to
arise from different directions and also at some distance from one another, so
as to form a well-balanced head.
2) The frame work is greatly strengthened, if the branches are spaced at about
15cm distance with medium crotches (40—500)
3) If two or more branches of equal size are allowed to arise from one place, they
form a bad crotch and often split from their common joint.

The most important systems of training followed in most of the fruit crops are:

Central Leader system:

 In this system, a tree is trained to form a trunk, which extends from the surface
of the soil to the top of the tree.
 In many kinds of trees, the central axis or the main branch naturally grows
vertically upwards and smaller side branches grow from it in various directions.
 If the central leader is allowed to grow indefinitely, it will grow more rapidly and
vigorously than side branches resulting in a robust close centre and tall tree. In
such a tree the bearing is confined in top portion of the trees.

Central Leader System

Merits and demerits:
1) The main advantage of this system is the development of strong crotches.
2) Its main disadvantage is shading of the interior of the trees.This weakens the
central leader and thus shortens the life of the tree
3) Since trees are very tall, harvesting and spraying become difficult and costly.

66
 4) The lower branches, which remain more or less shaded, become ultimately less
vigorous and less fruitful.
5) Owing to the shading of the inferior, the bearing surface moves to the periphery
(outer shoots) of the tree.Thus fruiting surface is reduced and eventually yields
are reduced.
6) The very high shape of the plants makes them prone to wind damage.
7) This method of training is not suitable for high altitude and hot arid places where
wind velocity is high.
This system is also called as close centre, since the centre of the plant is closed and also as
pyramidal system, since the plant trained looks like a pyramid.

This system of training is practiced in case of certain apple varieties and pears.

Open Centre system:

Open Centre system

 In this system of training, the main stem of the plant is allowed to grow only up
to a certain height by beheading it in the young stage ie.within an year of planting
and inducing all the subsequent vegetative growth by lateral branches
 This results in the low head in which the bulk of the crop is borne closer to the
ground than in case of central leader tree.

Merits and demerits:

1) It allows more light to reach all parts of the tree which is helpful (a) for better
colour development of the fruit (b) fruiting area is spread all over the area of the
trees.
2) Trees become low headed. So, pruning, spraying, harvesting etc., are facilitated.
3) The branches form weak and narrow crotches, which may frequently break under
severe stress and strain such as bearing of heavy crop and strong winds.
4) Sun scalding of central leader is also possible.
5) The branches form very close to each other all most from the same spot.
6) In this system the plants take a ‗‘bowl or vase‟‟ shape, which provides a good
base for setting of frost. So this system is not suitable for high altitude areas
where frost observance is common.

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 Since the main axis is removed, it leaves the centre open and hence open centre
and the tree looks like a vase (bowl), hence it is other wise called as vase
system.

This system of training is practiced in plums and peaches.

Modified Leader system:

 This is intermediate between the above two systems and has the advantages of
the both.
 This system is developed by first training the tree to the leader type allowing the
leader to grow unhampered for the first four or five years.
 The main branches are allowed to arise on the main stem at reasonable
intervals.
 After the required number of branches has arisen, the main stem is headed
back and lateral branches are allowed to grow as in the open centre system.
Merits and demerits:
1) This results in a low-headed tree with well-spaced limbs, well distributed fruiting
wood and low height to carryout orchard operations conveniently.
This system of training is practiced in fruit plants like citrus, pear, apple and walnut etc.

Which system of training is the best?

Among the above three systems of training, the modified leader system is the best and most
desirable because:

 Narrow to medium crotches and there by breakages are eliminated

 The indeterminate growth of the central axis is also prevented keeping the tree
height under control, so as to make orchard operations easy and cheap.
 No danger of sun scorching and fruit quality is good.

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Principles of training:
Irrespective of the system of training practiced, the following general principles are to be
observed:

1) The branches should arise on the main trunk alternatively at intervals of at least
15cm and not all at one place.
2) They should be equally distributed around the stem.
Up right branches should not be encouraged. Branches should have medium crotches.

Lecture 23: Pruning-Definition –Objectives of Pruning- Response of plant to pruning-Methods of Pruning-

Thinning out, Trimming, Heading Back, Pollarding, Pinching, Disbudding, Deblossoming -Season of
Pruning - Pruning and Manuring, Care of Pruned wounds.

Pruning may be defined as the removal of any excess or undesirable branches, shoots, roots, or
any other parts of a plant, so as to allow the remaining parts to grow normally or according to the
desire of the pruner.
Pruning is the removal of unwanted, surplus annual growth, dead, diseased, dried and broken
branches of the plants
Pruning is an art of removing scientifically certain portions of a plant with a view to producing more
and superior quality of fruit. Pruning of any kind according to its severity, changes the nutritive
conditions with in the tree and consequently, limits or encourages fruit bud formation.
Reasons for pruning

 There always seems to be surplus branches on a tree. But only those, which are useful to
the plant in holding up the leaves to the sun to grow strong. Those which will have little
chance of doing so, because of shade or other reasons become weak and eventually dry
up. Evidently the plant is making a selection and eliminating the useless branches. But this
process of selection and elimination is a slow one. Till they are eliminated the useless
branches also draw some nutrients which is a waste for the tree ultimately. If such branches
are recognized and eliminated earlier will help in conservation of food in the tree for better
production.
 The second reason for pruning will be the removal of diseased twigs to check the spread
of diseases
 In some fruit trees, fruits are borne on current flush (Ber, Grape etc.) which will be obtained
in large number after pruning of certain no. of old branches.
Objectives of Pruning:

1) To remove the surplus branches and direct the sap flow in to the remaining
branches.
2) To develop a strong frame work which can carry the load of a good crop and
can with stand strong winds.
3) To train the plants to a definite shape. Ex. Fence, Hedge, Topiary etc.

69
 4) To thin out branches so as to admit more light into the interior of the tree top so
that the inner wood also becomes fruitful.
5) To limit the size of the tree top to a convenient one so as to render spraying
and picking more easy and economically.
6) To regulate the spacing and distribution / direction of branches.
7) To distribute the fruiting wood in all directions and to maintain a balance
between vegetative and reproductive phases.
8) To improve the growth of the spur (A short lateral branch one inch or less in length
with nodes close together, so that the leaves converge to form a rosette ) shoots and
production of more flower buds.
9) To check the further spread of the diseases.
10) To maintain the vigour of the plant by removing the water shoots and other
unwanted growth.

Responses of plants to pruning:

The response of plants to pruning should be well understood for successfully achieving the object
of pruning. The following are the some of the important ways in which the plants show response
to pruning.

1. Activation of buds: When a branch is cut or pruned, the buds on the branch below the cut are
invigorated (activated). The bud close to the cut is most vigorous and this vigour decreases in the
buds as the distance increases from the cut. This is due to the elimination of the apical dominance
of the terminal bud from which the auxin flows down and inhibits the growth of the lateral buds.

This response is made use of to determine the direction of the existing branches and correcting a
crotch. If the crotch is a narrow (The angle between the branch and the stem on which it arises –
Crotch), the branch is pruned to an outer bud, so that the bud will produce a branch towards the
outer side usually at right angles to the branch or nearly so. As it grows larger, it pulls away from
the stem and eventually widens the crotch. Similarly, a wide crotch can be narrowed down by
pruning the branch to an inner bud.

2. Dwarfing response: The immediate effect of pruning is no doubt invigoration of new branches
owing to the diversion of food, but due to removal of much foliage, there is an overall reduction in
the manufacture of food resulting a shock on root growth This in turn limits the further growth of
the new shoots .When the growth of the new shoot is reduced, their length is also reduced.
Therefore, the net effect of pruning a tree is dwarfing, which is in proportion to the severity of
pruning. Both the spread of the top as well as the spread of the root system are reduced. This
also results in dwarfing of the plant.

3. Production of water shoots: Severe pruning often activates resting or adventitious buds and
buds on old wood may some time be stimulated to grow. They often produce branches, which
grow vertically and very vigorously with long internodes; angular stems large succulent leaves
and thorns (as in citrus). They are called water shoots or water suckers or bull canes. These
highly vegetative water shoots are seldom fruitful till they are several seasons old. They are
wasteful and unwanted because they draw much food and grow at the expense of the fruiting
70
wood and are better removed as soon as they appear. However, they may be profitably used in
some instances to fill in the gaps occurring in trees by lopsided development or loss of branches
due to other causes. Eg.Citrus,Guava,Ber,Sapota,cashew etc.

4. Delay in bearing: When pruning is severe particularly in early years of the fruit plant, bearing
is delayed. Some times severe pruning may also lead to poor yields, because a major portion of
the foliage and fruiting wood are lost.

Methods of pruning

1. Thinning out: When a shoot is removed entirely from the inception (from the point of origin) so
that, no new shoot arises from that place, it is referred as thinning out. This thinning is practiced
in the removal of shoots arising in unwanted places, water shoots etc.

2. Trimming: Cutting the growth of the twigs to a pre-determined level as in the case of fence,
hedge and edge.

3. Heading back: When the branches grow tall and vigorously without producing flowers, these
shoots are headed back. When a branch is cut almost to the base, leaving a few inches of stump,
carrying few buds, it is referred as Heading Back. These buds left on the stump will give rise to
shoots which are important to the tree either being spur bearers or bearing flower buds or filling
up of gaps in the tree or forming vegetative wood from which flowers may arise in the following
year. The shoot from the bud nearest to the cut takes the place of the pruned shoot.

4. Pollarding: Mere cutting back of the shoots, indiscriminately to reduce the height of the tree is
Pollarding.

5. Pinching (tipping): Removal of the tip of the shoot to stop its indeterminate growth or to
encourage the growth of the lateral buds is pinching or tipping. This is practiced in marigold
and chillies at the time of transplanting.

6. Disbudding (nipping or rubbing): Nipping or rubbing of young buds preventing a chance of

their sprouting is disbudding. When the buds arise in wrong places they are rubbed off. Similarly
sprouts (Buds) on root stocks are disbudded.

7. De-blossoming: Removal of surplus flowers to enable the tree to produce crops regularly year
after year is called deblossoming.This is practiced in alternate bearers like mango. apple etc.

Seasons of pruning:

1. It depends on the type of wood, type of plant species and time of flower bud
formation.
2. Removal of diseased, dead, and dried wood as well as water shoots can be
carried out at any time of the year.
3. Pruning of healthy branches should not be done when the trees are in flowering
or fruiting, since the resulting disturbance leads to loss of blossoms or fruits.
4. In deciduous trees, pruning can be done before the termination of dormancy.
5. In ever greens, pruning should be carried out before the start of active growth or
after the harvest of the crops.

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 6. Summer pruning of deciduous trees and also the pruning of evergreens in the
active growing season delays the formation of flower buds by prolonging
vegetative growth.
Pruning and Manuring:

The sudden invigoration of a number of buds due to pruning makes a demand on the food resource
of the tree, because the new shoots are not yet ready to manufacture their own food. The reserve
food in the plant often may not be sufficient to meet this demand of new growth. Further, pruning
means loss of much foliage and wood. So, to compensate the loss incurred due to pruning and to
meet the demand of new shoots the pruned trees should be manured heavily, otherwise the new
shoots ultimately wither and dry. This is particularly important when old (Senile) or neglected trees
are pruned for rejuvenation.

Care of pruned wounds:

Pruning leaves wounds and cut ends which should be protected to avoid the access of disease
pathogens and insect pests through these wounds and cut ends .So, immediately after pruning,
these cut ends and wounds should be protected by applying disinfectants like Bordeaux paste or
blitox paste.

Lecture 24: Unfruitfulness in fruit trees, Causes-Environmental causes, Nutritional causes,

Inherent causes, Biological causes, and cultural causes and their remedies.

Unfruitfulness is when a plant is unable to flower or bear fruit. Unfruitfulness is a major problem
in many fruit crops and their varieties result in huge loss to growers and make fruit cultivation less
profitable. Unfruitfulness in fruit crops refers to the state where the plants not capable of flowering
and bearing fruit.
1. Environmental causes:

1) Some varieties of a fruit crop don‘t flower in a locality owing to undetermined environmental
factors eg. several north Indian varieties of mango have not flowered in south India. This can be
remedied by top working with south Indian varieties.

2) Unfavourable temperature may cause failure of any flowering as in the case of apples in conoor
due to lack of sufficient winter chilling. It has been remedied to certain extent by oil emulsion
sprays and DNOC (Di-nitro-ortho cresol).

3) In tropics, plants flowering in summer may experience retarded pollen germination due to high
temperatures and low humidity. The provision of wind breaks, close planting and cover cropping
help in improving the situation.

4) Reduced illumination due to close planting ,over crowding of branches or shade will often
reduced flowering Thinning out some trees to increase spacing, pruning trees to reduce over
crowding and removal of shade can meet the situation.

5) When long day plants of northern latitudes don‘t flower owing to the absence of the critical
length of day, they can be made to flower by providing artificial light. On an orchard scale such
treatments are not practicable.

6) Late rains may prolong the vegetative growth and delay or reduce flowering in mango. It can
be remedied by drying out the soil by deep ploughing and probably by artificial inhibition of growth
by growth regulators.

7) Heavy rains may restrict pollinator activity, wash away pollen and prevent pollen germination.
Choice of varieties which don‘t flower at such periods of the year is the best way out. In crops like
72
grapes, the pruning time may be altered to avoid the onset of flowering during the period of the
rainy season crop may altogether be avoided by hard pruning.
2. Nutritional Causes:

1) Heavy nitrogenous manuring at the time of flower bud initiation often reduces flowering by
promoting vegetative differentiation. The practice should be given up. Root pruning and restricted
irrigation may be helpful in reducing vegetative vigour and inducing formation of male flowers.

2) Over bearing in the previous season exhausts the tree and reduces subsequent flowering as
in mango and most biennial bearing trees. A complete manure mixture applied at the growth flush
following the harvest will be helpful (June manuring in mango).

3) Lack of nutrition as in weak shoots causes fall of flowers before and after fruit set. A spray of
urea after fruit set will help the development of fruits.

4) Lack of sufficient reserves of carbohydrates in shoots may cause sparse flowering and poor
set (shoot bunches of grapes).Ringing and girdling may help. But it should not be continued as a
regular orchard practice.

5) Adverse growth features like water suckers will result in a drain on the tree and reduce
flowering not only on themselves but also on other branches of the tree. Such shoots arise when
big branches are pruned. Then it is necessary to cut big limbs, they should always be set to a
strong lateral but not stimulate a dormant bud. Late irrigation following a long drought may cause
the production of water shoots .The first irrigation after a drought should always be sparing later
ones being more liberal .When water suckers are formed due what ever reason, they should be
promptly removed.

6) Deficiencies of elements are sure cause of reduced flowering as well as set. A composite
mineral spray at flush time will usually be very helpful. If deficiency is due to alkalinity of the soil,
suitable reclamation measures should be adopted.

7) Heavy manuring and severe pruning during the pre-bearing period will prolong it. Pruning
should be done while branches are young, preferably by rubbing of axillary buds themselves by
frequent observation of the plants.
Seedlings and some species of plants have a long prebearing period during which no undue
anxiety should be felt for hastening flowering.

Old trees suffer from inadequate nutrition especially when they are neglected. The short extension
of shoots, small leaves showing various deficiencies, scanty leaves and die back of shoots indicate
approaching death. Such trees may be given one chance to bear by (1) manuring them heavily
with a complete mixture of nutrients (2) pruning hard up to 3-4 year old wood and (3) spraying a
composite mineral mixture on young flush. Irrigate frequently and protect them from pests and
diseases. This may rejuvenate the tree for a few years.

3. Inherent Causes:
1) Low proportion of female or perfect flowers as in some varieties of mango (Jehangir, Allampur
baneshan etc.) often is the cause for a poor crop. There appears to be no remedy for this defect.

2) Structural features like heterostyly and habits like dicho-gamy some times restrict the
availability of pollen and pollination. The presence of sufficient population of the tress and
pollinators ordinarily ensures good pollination and set.

3) Inadequate quantities of pollen appear to reduce fruit set in some varieties of strawberry and
some varieties of grape. Use of suitable growth regulators to get fruit setting will circumvent the
difficulty.

4) Many varieties of Japanese plums and apples are self sterile. Many other fruits also partially
self sterile .So planting varieties which make them fertile with their pollen will solve the problem.

73
 5) When intersterility is the cause for low fruit set compatible pollenizers have to be provided.
Mixed pollen sprays and use of synthetic growth regulators may also be helpful.

6) Triploidy and distant cross are often reasons for low fruit set. Chemical aids can get over the
problem.

7) Defects of ovule development, embryo abortion etc.are observed in dropped flowers. These
largely seem to be varietal characteristics and cannot largely be altered.

4. Bio-logical causes:

1) Absence of pollinating agents can be a reason for low fruit set in several fruits. Rearing bee
colonies in orchards, besides being a subsidiary source of income greatly helps fruit set.
2) When specific insects‘ symbiotic adaptations (like the blastophaga for fig) concerned with the
pollination, they must be reared (by growing Capri fig trees in this case). A wooden needle
seems to perform the duties of the blastophaga quite as efficiently in promoting set of fig fruit.

3) Pests like the mango hopper which directly attacks the flowers obviously reduce the fruit set.
Others which feed on leaves reduce the photosynthetic surface impair production of carbohydrates
and thus reduce flowering. Several fungal diseases do the same thing; Suitable remedial measures
should be taken to protect the tress.

5. Cultural causes:

1) The commonest cause of poor flowering in house gardens is excessive irrigation which restricts aeration
of roots and causes sickly symptoms. Increase of intervals of irrigation and provision of drainage are the
remedies.

2) Weeds and intercrops may compete with the main crop for nutrition and water in low rainfall areas
.Removal of weeds and adequate manuring to meet the demands of both the fruit crop as well as the
intercrops are helpful. Intercrops which clash with the irrigational and manurial requirements of fruit crops
both in respect of quality and time of application should be avoided.

3) Ploughing or deep cultivation at flowering time will result in drop of flowers and should be avoided.

4) Severe pruning of large limbs which encourages production of water shoots should be avoided. If it is
absolutely essential, the branches may be cut to a strong lateral. Wrong pruning techniques may also
cause reduction of flowering. The following points should be borne in mind (1) the pruning should be with
regard to bearing habit of the fruit tree, (2) the pruning should be up to some fruitful buds (in
grapes).Harder or light pruning will reduce fruiting, (3) a balance of vegetative and fruiting wood should
be maintained in plants bearing on past seasons wood, (4) pruning should not be delayed till the new
growth is resumed.
5) In practice good drainage, timely irrigation, manuring and culture and selection of suitable varieties will
ensure good set of crops.

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 Lecture 25: Pollination, Pollinizers, and Pollinators –problems and role in horticulture
production.
Pollination refers to transfer of pollen grains from anther to stigmatic surface. It is of two
types viz., self-pollination and cross-pollination.
If the transfer is from stamen to stigma of the same flower or to the stigma of another
flower on the same plant or to the stigma of a flower on any plant of the same clonal
variety, then this type of pollination is known as 'self-pollination’.If it is effected without
the aid of any outside agency, such as wind or insect, then this process is known as
'autogamy’.
If the pollen is to be transferred to the flower of another individual or in the case of
pomological varieties, to the flower of another variety, this process in known as 'cross-
pollination' or allogamy.
Cross-pollination may be required for a number of reasons in Horticultural crops.

1. Due to the dioeciously nature (eg. Papaya, Datepalm, Nutmeg) or monoecious

nature (Cucurbits)
2. Due to the peculiar flo\ver structure, (eg. Brinjal, Delicious apples, Vanilla)
3. Due to the dichogamy nature (Onion, Carrot, Sapota)
4. Due to the behaviour of bisexual flowers as functionally unisexual (eg. Avocado
and Allspice)
5. Due to self-incompatibility or self-sterility factors (eg. Apple).

 The pollen may be transferred from the anther to the stigma in a variety of ways. In most
plants, pollen is shed at or after anthesis and is transferred to the stigmas by insects or by
mechanical means primarily the wind.

 In majority of the horticultural crops, pollination is effected by insects and pollination by

wind is not a common one.

 Fruit crops like sapota, jack and amla and nutcrops like walnut, chestnut and
pecans are reported to be pollinated by winds.

 They normally produce large quantity of pollen grams which are light in weight so that they
can be carried to distance places. In these nutcrops, the stigma is also feathery to facilitate
wind pollination.

 Honey bees, ants and many insects aid in cross-pollination. Their activity is greatly
affected by weather conditions especially low temperature and rain which sharply curtail
their activity. Hence, honey bee keeping is important.

 In apple orchards, each honey bee usually forages 2-3 trees and visits 50-100 flowers per
trip. Thus in a day, it visits about 50000 flowers. Hence, 10-12 colonies per hectare at. a
distance of 150 metre are ideal for temperate fruit orchards.

 Recently, a chemical substance (Ex. Bee-Q) is used to attract the bees so as to increase
the fruit set. It has been estimated that nearly double the number of flowers are pollinated
75
 in cardamom if such chemical is used at the time of early and mid flowering phases.

Artificial pollination

 Self-incompatibility is common in apple and pear. This has been recently overcome with
the 'recognition' or 'mentor pollen' technique.

 In this technique, pollination is effected with a 2:1 mixture of Methanol killed or irradiated
compatible pollen and self pollens which results in seed set.

 It is believed that the regualtory sub stance from the mentor pollen to the in
compatible/incongruent pollen helps to overcome the crossing barriers.

 Another technique viz,`pioneer pollen' is also reported to increase the seed set in such
Fruit crops'

 In this method, pollination twice with compatible pollen with an interval of 1-2 days is done.
It appears that the first applied pollens promote the activities of the pollens in the second
application, hence the first applied pollen is called 'pioneer pollen'.

 In emergent situations, when adverse weather conditions prevail or the orchard has
inadequate pollinizers, hand pollinaion can be resorted to.

 This is much helpful in temperate fruit orchards and is being practised in European
countries and not yet in India.

The following are some of the methods by which artificial pollination is done.

1. Artificially collecting the pollens, mixing it with spores of Lycopodium (fern) and applying
to flowers with a soft brush.

2. Placement of bouquets - in this method, branches of flowers of pollinizers are hung in the
trees to be pollinated.

Pollinizer:
A plant that is a source of pollen called pollinizer. For example, most crab apple varieties
are good pollinizers for any apple tree that blooms at the same time, and are often used in apple
orchards for the purpose. Some apple cultivars produce very little pollen or pollen that is sterile or
incompatible with other apple varieties. These are poor pollinizers.
Pollinators:
A pollinator is the biotic agent that moves the pollen, such as bees, moths, bats, and birds.
Bees are thus often referred to as 'pollinating insects'.
Pollination problems in horticulture:
o Insufficient pollinator activity: When there are not enough pollinators to visit flowers
adequately, leading to poor fruit set.
o Weather constraints: Adverse weather conditions like rain or strong winds can hinder
76
 pollinator activity.
o Flower morphology issues: Certain flower structures may be difficult for pollinators to
access, impacting pollination efficiency.
o Crop isolation: Planting only one variety of a crop can limit cross-pollination, affecting
fruit quality.
Impacts of pollination problems:
o Reduced fruit set and yield: Fewer fruits developing due to inadequate pollination
o Deformed fruits: Poorly pollinated fruits may have misshapen or smaller sizes
o Reduced seed viability: Lower seed quality and germination rates
Management strategies for pollination in horticulture:
o Enhance pollinator habitat: Planting flowering plants to provide nectar and pollen
sources for pollinators
o Honeybee hive placement: Strategically placing beehives within the crop area to
maximize pollination
o Hand pollination: Manually transferring pollen from male to female flowers in situations
with limited pollinators
o Crop selection: Choosing varieties known to be self-pollinating or compatible with local
pollinator populations
o Pesticide management: Minimizing pesticide use that may harm pollinators

Lecture 26: Juvenility-Definition, Flower bud differentiation-Influence of various factors on flower

bud initiation. Environmental – Chemical –Nutritional - managemental. Types of Buds,
Fertilization- Definition and Types of Fertilization and Apomixis.

Juvenility:

After seed germination, annual and perennial seedlings enter a rapid growing phase in which
flowering cannot be induced. The juvenile phase is defined as a physiological age where the
plant cannot flower even though the environmental conditions are suitable for flower induction.

Sexually propagated plants have long juvenile (pre-bearing) period. Vegetatively propagated plants
are more precocious in bearing (flower earlier than seed propagated plants). Pre-bearing period is
less. No juvenility. For example, seed propagated mango plants take at least 8-10 years to flower,
where as grafts flower within 3-4 years.

Flower bud differentiation:

Plant process by which the shoot apical meristem changes its anatomy to generate a flower or
inflorescence in lieu of new nodes with leaves. Anatomical changes begin at the edge of the
meristem, generating first the outer whorls of the flower – the calyx and the corolla, and later the
androecium and gynoecium. Flower differentiation can take from only a few days (in annual plants)
to 4–11 months (in fruit crops). The process is preceded by flower induction.

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Influence of various factors on flower bud initiation:

Flower initiation is an important transition from vegetative growth to reproductive growth and is also
a determinate stage in plant yield formation. Flower bud initiation is significantly impacted by a range
of factors including photoperiod (day length), temperature, plant nutrition, water availability, plant
age, plant vigor, hormonal balance, stress levels, and cultivar characteristics; with many of these
factors interacting to determine the timing and quantity of flower buds formed on a plant.

1. Environmental factors:

Photoperiod:Many plants require specific day lengths to trigger flower bud initiation, with some
plants flowering under long days (long-day plants) and others under short days (short-day plants).

Temperature:Optimal temperatures vary by species, but generally, cooler temperatures can

promote flower bud initiation, while extreme heat can inhibit it. A range of subtropical and tropical
tree species can be induced to flower by exposure to low temperature Ex. Mango

Water availability:Water stress can often induce flowering in some plants by triggering hormonal
changes, but severe drought can hinder flower bud development.

2. Plant factors:

Plant age:Younger plants tend to focus on vegetative growth, while mature plants are more likely to
initiate flower buds.

Plant vigor:Excessive vegetative growth (high vigor) can delay flower bud initiation, while moderate
vigor is often optimal for flowering.

3. Nutrient status:

Adequate levels of essential nutrients, particularly phosphorus and potassium, are crucial for flower
bud development. Nutrient deficiency, especially nitrogen (N) reduces the extension of leaf area, as
a consequence of a prolonged time of dry matter accumulation.

4. Hormonal balance:

Plant hormones like cytokinins promote vegetative growth, while auxins and gibberellins can
influence flowering depending on their concentration and interaction.

5. Other considerations:

Cultivar differences:Different cultivars within a plant species can have varying flowering responses
to environmental cues.

Stress factors:Environmental stresses like extreme temperature fluctuations, nutrient deficiencies,

or pest infestations can negatively impact flower bud initiation.

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Pruning practices:Pruning can influence flower bud formation by manipulating the plant's growth
habit and carbohydrate reserves.

Importance of proper management:

Understanding the factors affecting flower bud initiation is crucial for maximizing flower production
in horticultural practices.

To induce flowering in mango is temperature below 15–20 °C, with florally inductive temperatures
varying between cultivars. Floral initiation is affected by the cycle of flush development, and the
timing and intensity of flowering can be manipulated by exogenous applications of PGRs.

Types of Buds: Buds are often useful in the identification of plants, especially for plants in winter
when leaves have fallen. Buds may be classified and described according to different criteria:
location, status, and function.

Based on location: 1. Terminal buds: when located at the tip of a stem.

2. Axillary buds: when located in the axil of a leaf.

3. Adventitious buds: when occurring elsewhere, for example on trunk or on roots.

Based on status:

1. Accessory buds: the secondary buds formed besides a principal bud (axillary or terminal).

2. Resting buds: the buds that form at the end of a growth season, which will lie dormant until onset
of the next growth season.

Based on function:

1. Vegetative buds: the bud only containing vegetative pieces that is embryonic shoot with leaves
(a leaf bud).

2. Reproductive buds: the containing embryonic flower(s) (a flower bud).

3. Mixed buds: the containing both embryonic leaves and flowers.

Fertilization:

It is the union of male and female gametes (reproductive cells) to produce a zygote (fertilized egg).
Fertilization in angiosperms is a complex, somewhat unusual process in which two sperm cells are
utilized in a unique process called double fertilization. Double fertilization results in two key
developments: (1) the fertilization of the egg, and (2) the formation of a nutrient substance called
endosperm that nourishes the embryo. Once fertilization is complete, the embryo develops by
dividing numerous times. Meanwhile, protective tissues enclose the embryo, resulting in the
formation of the seed.
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Types of Fertilization: 2 types.

Porogamy: This is the commonest type of fertilization seen in angiosperms here the entry of the
pollen tube into the ovary takes place through the microphyle.

Chalazogamy: In plants like casuarinas, the entry of pollen tube takes place through the chalaza.

Apomixis:
It is the occurance of an asexual reproductive process in place of normal sexual reproductive
process of reduction division and fertilization. Simply, it is an asexual seedling developed from a
seed viz., a seedling that arises from tissue of the seed other than embryo.
Plants that produce only apomictic embryos are known as obligate apomicts, (Eg. Mangosteen)
those that produce both apomictic and sexual embryos are facultative apomicts eg. Acid lime
Type of apomixes:
Recurrent apomixes
Here, embryo develops from the egg mother cell which doesn’t under go any meiosis. So., egg has
normal diploid number of chromosome. The same as in the mother plant. The embryo subsequently
develops directly from the egg nucleus without fertilization. In some cases, the embryo develops
with stimulus of pollination (eg. Allium) and in some cases, without stimulus of pollination (eg.Malus)

Adventitious or Nucellar embryony

Here, embryo will rise from a cell or group of cells either in the nucellus or in integuments. Here,
embryo develops outside the embryo sac in addition to the regular embryos. Eg. Citrus
Nonrecurrent apomixes
Here embryo arises from the egg nucleus without fertilization. Since the egg is haploid, the resulting
embryo will also he haploid. The case is very rare.
Vegetative apomixes
In some cases, vegetative buds or bulbils are produced in the inflorescence in place of flowers eg.
Agave and grass species
Polyembryony
The phenomenon in which two or more embryos are present within a single seed is called
polyembryony (Nucellar embryony)
Significance of apomixes
1. Apomictic seedlings are true to its mother and apomictic cultivar can be considered as a clone
2. They are uniform and vigorous
3. Virus diseases are not seed borne. So, it is the best method to rejuvenate
virus affected plant crops.

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Lecture 27: Parthenocarpy-Definition and Types of Parthenocarpy.

Parthenocarpy:

The process where fruits are formed from a flower without the process of fertilization is called
Parthenocarpy.

Parthenocarpy (literally meaning a virgin fruit) is the natural or artificially induced production of fruit
without fertilization of ovules. Seedlessness is a desirable trait in edible fruits with hard seeds
(pineapple, banana, orange, grapefruit) also desirable in fruit crops that may be difficult to pollinize
or fertilize. In dioecious species (e.g., Persimmon), pathenocarpy increases fruit production as
staminate trees do not need to be planted to provide pollen. Increases shelf life due to reduced
ethylene generated by seeds. Improves processing quality & ultimately increases profitability.

Seedless fruits are desirable for improving the quality of fresh as well as of the processed fruit and
it has been observed in cucumber, eggplant watermelon and tomato.

In cultivated plants, parthenocarpy is introduced with plant hormones such as gibberellic acid. It
causes ovaries to mature without fertilization and produces bigger fruits. It is also a natural process
as in the case of bananas. Bananas are sterile and develop no viable ovaries. They do not produce
seeds, which mean they must propagate vegetatively. Pineapples and figs are also examples of
parthenocarpy which occur naturally.

Parthenocarpy can be induced in many crops (cucumber, tomato, bottle gourd, brinjal, Cucurbita,
watermelon, etc.) by applying exogenous auxin gibberellins and cytokines and also auxin transport
inhibitors.

Types of Parthenocarpy: Two types

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I. Natural or genetic Parthenocarpy:

Natural parthenocarpy is a type of parthenocarpy that occurs due to natural causes such as male
sterility, adverse environmental conditions, the absence of pollinizers and pollinators, etc.

A. Genetic Parthenocarpy – obligatory: when expression of the Parthenocarpic trait is not

influenced by external factors

B. Genetic Parthenocarpy – facultative: occurs only under adverse conditions for pollination and
fertilization.

Elevated level of endogenous hormones in the ovary in the absence of pollination and fertilization
causes the natural Parthenocarpy. It has been reported in various crops like grape, tomato,
mandarins, banana, eggplant, cucumber. Genetic parthenocarpy can solve the problem of low pollen
viability and poor pollen release, which often occurs under low light, low or high temperatures under
open and greenhouse conditions.

Parthenocarpic cucumber does not require pollination, even though, it is a cross-pollinated crop.

C. Vegetative parthenocarpy: This type of Parthenocarpy takes place without pollination which
results in no seed production. It can be seen in pears and figs. Vegetative parthenocarpy occurs
entirely in the absence of pollination. Since pollination does not take place, the ovules remain
unfertilized, and no seeds are produced within the fruit. This type of parthenocarpy is often natural
and is observed in some plant species where seedless fruits are formed. Ex. banana

D. Stimulative parthenocarpy:

This also takes place without pollination, however, there is the usage of an external stimulator. This
can be the ovipositor of a wasp inserted into the ovary of a flower or the application of plant growth
regulators into unisexual flowers which are observed inside the syconium.

In fig, it occurs when a wasp inserts its ovipositor into the ovary of a flower. It can also be simulated
by blowing air or growth hormones into the unisexual flowers found inside something called a
syconium.

E. Stenospermocarpy:

This is a unique type of parthenocarpy where pollination and fertilization take place and the seed
begins to develop but it eventually aborts. There’s a seed trace that can be observed within the fruit
and it can be outlined where seed development was terminated. This type of Parthenocarpy can be
seen in seedless grapes and watermelons.

The exogenous use of irradiated pollen, natural or synthetic auxins and gibberellins increased IAA
content during ovary development.

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Parthenocarpy was completely achieved with CPPU @ 200 ppm and NAA @ 150 ppm in
watermelon.

II. Artificial / Induced parthenocarpy: is a type of parthenocarpy that is done by artificial

means. Artificial parthenocarpy can be done through irradiated pollen and with the spray of plant
growth hormones such as auxin and Gibberellins that help in the growth of the fruits.

Lecture 28: Maturity, harvesting, grading, packaging and storage of important fruits, vegetables and
flowers

Maturity
It is the stage of fully development of tissue of fruit and vegetables only after which it will ripen
normally. During the process of maturation the fruit receives a regular supply of food material from
the plant. When mature, the abscission or corky layer which forms at the stern end stops this inflow.
Afterwards, the fruit depend on its own reserves, carbohydrates are dehydrated and sugars
accumulate until the sugar acid ratio form.
Table 1: Criteria of maturity for harvesting fruits

Fruit Physical Chemical

Mango Olive green colour with clear lenticels, shoulder Starch content, peel/flesh
development size sp. gravity, days from fruit set. colour
Banana Skin colour, drying of leaves of the plant, Pulp/peel ratio, starch
content
brittleness of floral ends, angularity of the fruit,
and days from emergence of inflorescence.
Citrus Colour break of the skin from green to Sugar/acid ratio, TSS
orange, size
Grapes Peel colour, easy separation of berries, TSS
characteristic aroma 18-12 Thompson
seedless,
12-14 for Bangalore Blue,
14-16 for Anab-e-shahi
Apple Colour, size Firmness as measured by
pressure tester
Papaya Yellow patch or streaks. Jelliness of the seed, seed
colour

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 Root, bulb and tuber crops Maturity indices
Radish and carrot Large enough and crispy
Potato, onion and garlic Tops beginning to dry and topple clown
Yams, bean and ginger Large enough
FRUIT VEGETABLES
Cowpea, snap bean, sweet pea, Well filled pods that snap readily
winged bean
Lima bean and pigeon pea Well filled pods that are beginning to lose
their greenness.
Okra Desirable size reached and the tips of
which can be snapped readily, less fibre
Snake gourd and Bottle gourd Desirable size reached and thumbnail can
still penetrate flesh readily
Egg plant, bitter gourd, slicing Desirable size reached but still tender
cucumber
Tomato Seeds slipping when fruit is cut, or green
colour turning pink
Muskmelon Easily separated from vine with a slight
twist leaving clean cavity (full slip stage),
Netting on the skin
Watermelon (a) dull sound when the fruit is thumbed,
in contrast to metallic sound, (b) withering
of first tendril at the fruit axil, (c) ground
spot (where the fruit touches the ground)
turning yellow, (d) the rind of the ripe
melon emits a crisp, cracking noise
FLOWER VEGETABLES
Cauliflower Curd compactness
Broccoli Bud cluster compact
Harvesting:
Harvesting of vegetables at optimal maturity and careful handling constitute the very key to their
successful long storage life. Harvesting is done in two way viz., by hand, with or without mechanical
aids or gadgets and mechanical harvesting. In India, most the vegetables are harvested manually.
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 Root crops: Beet root, Carrot, Radish, Turnip and tubers like Potato, Tapioca and Sweet potato are
easily harvested by digging into the soil below the roots or tubers. then it is levered upwards so as
to loosen the soil and to reduce the possibility of mechanical damage.
Leaf vegetables: In spinach and methi, the lateral buds and they snapped off by hand. Cabbage,
cauliflower, knolkhol and lettuce: Here, the main stem is cut off with a sharp knife.
Bulbous crops: Green onions and leeks can be easily pulled out by hand from the moist soil
whereas for harvesting of fully mature onions and garlic bulbs, soil is loosened first with a fork or
how. simple tractor drawn implements are also available for loosening the soil in onion and garlic
like crops. Onion could be harvested. Harvesting og immature bulbs cause shriveling and rotting.
Delay in harvest cause splitting and bolting.
Tomato: Harvesting the fruits at breaker stage is recommended for long shelf life and optimum
quality. Harvesting during evening hours in summer keeps the fruit firm and uniform ripening is
effected.
Okra : Immature, green, tender fruits should be picked from 3 rd -5th day of first pod formation.
Brinjal: Brinjal is harvested at tender stage ie. 15-20 days after fruit-set when the seeds are
immature.
The fruit growers should bestow more attention and considerable care during the picking
season to reduce to a minimum level of careless handling of fruits by pickers
i Picking must be commenced from the lower branches of tree advancing towards the top in order to
reduce dropping of fruits to the minimum
ii As far as possible, dropping of fruits from the tree should be avoided to avoid any possible physical
damage.
iii During picking, care must be taken to avoid any possible damages to the branches especially to the
spurs as the subsequent cropping depends upon them
iv Picking early in the morning is always best. Picked fruits should be kept in shade and excluded from
sun. After picking, the fruits must be kept in the coolest place available which is well ventilated to
arrest respiration and break down as much as possible
v There should not be any bruises in the fruits while picking as it will lower the marketable quality
vi If picking is done in mid day or hot weather, fruits should be kept in a shed overnight to cool.

Handling
Handling includes all process from picking to deliver or disposal at the consumer point. this
includes the treatments given for getting the fruits ready for the market viz., packaging and wrapping,
ripening and storage. One of the important treatment is the dipping the fruit in antiseptic solutions
like 1-2% caustic soda to remove the dust and infestation of scale insects and washing with 1-15%
of Hydrochloric acid to remove any spray residue and to improve the appearance.
Pre-cooling : It refers to the rapid removal of the field heat from the freshly harvested fruits and
vegetables in order to sow ripening and reduces deterioration prior to storage and shipments.
Different methods are adopted to precool the fruits, the important ones are
1. Air cooling in which the fruits and vegetables in a cold room
2. hydro cooling-dipping of the fruits in cold water or by spraying cold water on the fruits and
3. vacuum cooling-a costlier technique in which the atmospheric pressure is reduced so as to reduce
the pressure of water vapour in chamber which results in evaporation of water from fruits which bring
down the temperature. Vacuum cooling about 1% weight loss in the produce.

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 Grading
Grades or grading refers to the assortment of the fruits into different groups based on
certain characters. this includes colour, condition to firmness and
soundness and free form blemishes and also size of the fruit. Grading is a good market
practice which improves the mutual confidence of salesman and consumer Agriculture prescribes
the following grades to apples in the USA
1. US Extra fancy
2. US Fancy
3. US No.1
4. US commercial

In India, grading of fruits like apple plum, pear and mango varieties like alphonso, rumani,
bangalora and sathugudi is done by agmark mainly based on size only.

Packaging and packing : The term packaging encompasses both the direct or primary packaging
around the product and the secondary and tertiary packaging, the over packaging such as over
warts, cartons and crates etc. Proper packaging is essential otherwise the spoilage of fruits and
vegetable are more in our country.
A packaging material should be sturdy and it should protect the fruits in transport, more specifically
it must be economical. The materials that are generally used in India for construction of a package
of fruits and vegetables are bamboo, wood, gunny bags, plastic, films, fibre and plast corrugated
boards etc. Bamboo baskets and wooden crates of different shapes and sizes are used for a
number of perishable commodities. Mud pots, gunny bags and palmyrah mats are also used for a
variety of purposes. In some cases like mango, pine apple, banana etc. a straight load is practiced
in certain regions. For example, banana in bunches are loaded without any packaging into the
railway wagons or trucks and transported from Maharashtra to Delhi. Similarly, mangoes are
transported form South to North and pineapples are shipped form North East India and Kerala to
different regions. In these cases, it has been observed that the loss due to spoilage are
considerable.
Storage
Storage of fruits and vegetables prolongs their usefulness, it is also check market glut, provide wide
selection of fruits and vegetables throughout the year, helps in orderly, marketing, increases profits
to the producers and preserve the quality of the living products.
The principal aim of storage is to control rate of transpiration, respiration and disease infection and
to preserve the commodity in its most usable form for consumers without proper storage, the
following undesirable things may occur
1. Sprouting: - e.g. onion, ginger, garlic, potatoes etc.
2. Rooting: - e.g. sweet potato, onion etc.
3. Seed germination: -e.g. pod bearing vegetables, tomato, papaya etc.
4. Degreening: -e.g. potatoes of exposed to light, green portion contain solanin which is toxic.
5. Toughening: e.g. Green beans, bhendi etc.

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Lecture 29: Flower and Fruit drop – stages, causes – remedial measures.

Fruit drop
Fruit trees usually bear a large number of flowers and only a small percentage of which
are enough to give a normal yield. For instance, a single inflorescence of mango contains as
many as 5000 flowers and an average of 5 fruits per inflorescence would provide a good and
heavy crop, however, the actual percentage of fruit set will be much lesser. When the fruit
set is much more that the tree can normally carry to maturity, there will be drop of fruits at
various stage of fruit development as an adjustment by the tree to its resources.
Stages of flower and fruit drops:
First drop
It occurs a fortnight later than the first flowering. Usually flowers with aborted pistils drop off
at this stage. Lack of pollination, low stigmatic receptivity, defective flowers, poor pollen
transference and occurrence of incompatibility are some of the causes attributed for this drop.
Second drop
It occurs a fortnight later than the first drop. This drop includes unfertilized flowers and
some fertilized flowers. Fertilized flowers also drop off at this stage as a result of adjustment
in the trees between nutritional factors and fruit set.
Third drop
This drop occurs when the fruits are of ‘marble size’ due to the formation of abscission
layers in the young fruit stalks. This drop generally occurs in most deciduous fruit and as it
coincides with the month of June, this drop is also know as ‘June drop’
Pre-harvest drop
Another kind of fruit drop which is a loss to the grower is referred as ‘pre-harvest’ drop. In this
case, dropping or shedding of fruits occur before harvest. At this stage, half-developed and
three-fourth developed fruits are shed due to many causes. This is a loss to a growers and is
a serious problem confronted by them especially in apples, pear mango and citrus fruits
Causes of flower and fruit drop:
1. Mechanical – Wind and hailstorm cause fruit drop
2. Climatic factors – Climatic factors such as high temperature, low humidity and very low
temperature hasten the formation of abscission layers and consequently the fruits drop. It
has been observed in South India that shedding of fruits in mango will be more if the
temperature is high and humidity is low.
3. Physiological factors – Abnormal fluctuations of soil moisture favour heavy fruit drop
4. Inadequate pollination: When pollination fails to occur, flowers deteriorate and drop
prematurely. Factors like rain and cold temperatures can hinder the activity of pollinating
insects, while excessively high temperatures can disrupt the pollination process.
Moreover, insect infestations, and diseases can also impede proper pollination.
5. Nutritional – Lack of available nitrogen and other nutritional factors may causes fruit drop.
The shed is more in weak shoots than in strong ones and also more in young trees than
in medium or old trees.
6. Cultural practices – Deep digging or deep ploughing during the fruit development phase
will injure the roots and cause the fruit to be shed. Drought or lack or irrigation especially
in mango during the third drop stage increases the dropping percent.
7. Pathological causes – Incidence of pests and diseases will cause more shedding of fruits.
For instance, high incidence of diseases like powdery mildew and anthracnose and pests
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 like hopper and mealy bugs in mango favour more fruit drop
8. Varietal factor – Within a kind of fruit, the varieties differ among themselves in the extent
of fruit drop. In one study, it has been found that under similar conditions, the extent of
shed varied form 0.9% in Willard variety to 32.5% Jehangir variety of mango
Remedial measures:
1. Regular Watering: Ensuring trees receive sufficient and consistent watering can alleviate
plant stress and minimize fruit and flower drop.
After mango fruit setting, at pea stage a light irrigation will reduce fruit drop.
2. Proper Nutrition: Utilizing appropriate fertilizers can bolster tree health, fortifying flowers and
fruits against premature drop.
3. Pest and Disease Control: Regularly inspecting trees for pests and diseases and employing
suitable control measures can reduce fruit drop.
4. Fruit Management: Avoid excessive fruit production to curb fruit drop. Pruning trees to
maintain a balanced fruit-to-tree capacity ratio is essential. Trimming trees and removing
diseased or dead branches promotes tree health, ensuring robust fruit production in
subsequent seasons.
5. Utilization of Plant Hormones: Plant hormones like ethylene can be effective in regulating
fruit drop. Seeking guidance from experts in this field can be beneficial.
6. Mitigating Environmental Stress: Enhancing environmental conditions such as light
exposure, temperature, and humidity can alleviate tree stress, reducing the likelihood of fruit
and flower drop.
7. Harvest Timing Adjustment: Harvesting fruits at the optimal time can help minimize fruit
drop, ensuring a more successful yield.
8. The pre-harvest drop may be reduced by providing wind breaks will help to prevent or
reduce the amount of fruit drop
9. A define relationship between the auxin content and the abscission of fruits during
various stages of development has been established is apple fruits. In the final stages
of fruit growth, a rapid decline in auxin content is correlated to degeneration of
endosperm causing preharvest fruit drop. This led to the thought that high concentration
of auxins supplied exogeneously may inhibit fruit drop
10. The possibility of reducing the preharvest drop by means of plant regulator sprays has
been well established in many fruit crops. Napthalene Acetic acid and its related
compounds are very effective in reducing the drop of fruits in many fruits.
Ex. Mango – NAA 1ml/4.5 L of water
Sweet orange – 2,4D – 1mg in 100 L of water

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Lecture 30: Role of bio regulators in Propagation- Control of Flowering, Fruit set, Fruit drop,
Parthenocarpy, Fruit ripening, Fruit size, quality and Sex expression.

Growth and development of the plant body are controlled by two sets of internal factors, namely,
nutritional and hormonal. Nutritional factors supply the plant necessary mineral ions and organic
substances such as proteins, carbohydrates and others. These constitute the raw materials
required for growth. However, utilization of these substances for proper development of the plant
is controlled by certain chemical messengers, called plant growth substances or plant growth
regulators, which in minute amounts increase or decrease or modifies the physiological processes
in plants.

The term plant growth regulators is relatively new in use. In earlier literature these were mentioned
as Hormones. Hormone is a Greek word derived from hormao which means to stimulate. Now
the term phytohormone is used in place of plant hormone.

Plant growth regulators or plant regulators are the organic compounds other than nutrients which
modify or regulate physiological processes in an appreciable measure in the plants when used in
small concentrations. They are readily absorbed and these chemicals move rapidly through the
tissues when applied to different parts of the plant.

Plant hormones or phytohormones are also regulators but produced by the plants in low
concentrations and these hormones move from the sit of production to the site of action. Therefore,
the difference between the plant regulator and plant hormone is in that the former one is synthetic
and the latter one is natural from the plant source.

The various types of growth regulating substances are:

Auxins, Gibberellins , Cytokinins, Ethylene and Abscisic acid

Auxins, Gibberellins and cytokinins are Growth promoters and Ethylene and Abscisic acid are
growth inhibitors. Growth Retardants: These are chemicals which have common physiological
effect of reducing stem growth by inhibiting cell division.

Growth regulating substances have many practical applications in horticulture and some of the
most important uses are:

1, Propagation of plants: The most common use of plant regulators in horticulture is to induce
rooting in stem cuttings and in air and soil layers.
Rooting of cuttings: Certain kind of plants may not successfully root under normal condition and
with the aid of plant regulators; they can be easily made to induce rooting. The most commonly
employed growth regulators for rooting are auxins like IBA, IAA, IPA and NAA. Among these
chemicals IBA is most ideally used since, it is the most effective one.
Concentrations ranging from100-500ppm are used for long dip method of treatment of cuttings for
12-24 hours and high concentrations of 10,000 to 20,000 for quick dip method for a few seconds.
The concentrations differ according to the type of cutting i.e. herbaceous, Semi-hard wood and hard
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wood cuttings. Applications in the form of dust as talcum preparation or in the form of a paste in
lanolin are also used.
Layering: Another usage of plant regulators in plant propagation is in aiding rooting of air layering.
When the ring of bark is removed from the stem, the growth regulators like IBA or IAA in power or
in Lanolin paste is applied at the distal end of the bark-removed portion to promote root formation
Grafting and Budding: In grafting when the cambium of a stock plant comes into physical contact
with the cambium of a scion both from new xylem and phloem simultaneously together.
Consequently, these become united and grow as one plant. Since, auxins have the property of
promoting cell division of cambium these are often employed. Before grafting, either stock or scion
or both are dipped in auxin solution. This promotes an early union and consequently, a better
success of grafted plants.

Control of flowering: The plant growth regulators are used for the regulation of flowering in certain
crops. In pineapple flowering is irregular and harvesting becomes a problem and hence to regulate
flower production, plant regulators are used. The treatment generally consists of pouring a required
quantity of (50ml), the solution containing 0.25 to 0.5 mg of the chemical of NAA in the central core
of plants. In recent studies, Cycocel and Alar at 5000ppm and Ethrel at 100-200ppm have been
shown to induce flowering in mango during an off year. In Jasminum grandiflorum, the flowering
period is extended by the application of Cycocel at 500ppm.
Flowering can also be induced in certain vegetables such as radish, beet root and carrot with the
application of GA.

Fruit set: Various growth regulators like IAA, IBA, IPA, NAA, 2, 4-D, 2, 4, 5-T and GA have been
found to improve fruit set in many crops. Among these chemicals 2, 4-D and NAA (Planofix) have
been found in general to be most effective in increasing the fruit set. The optimum concentrations
for this purpose are 10-20 ppm of auxins and 10- 100ppm of GA in different crops. Spraying the
flower cluster thoroughly 4-6 days after full bloom with 100 ppm GA increased the fruit set in grape.
It has been found that in chillies spraying of Planofix @ 1ml in 4.5 litres of water at 60th and 90th day
after planting is beneficial for good fruit setting.

Fruit drop: Losses resulting from pre-harvest drop of fruits have long been a serious problem.
When the growth regulators have been put in to use in apples and pears, pre- harvest fruit drop can
be checked by the application of 2,4-D and 2,4,5-T effectively. Pre harvest fruit drop in citrus is
controlled with 2,4-D at a concentration of 20ppm2,4-D, 10- 15ppm of NAA and 2,4,5-T at 15 to
30ppm at pea stage and marble stage and 2,4D at 20ppm and 2,4,5-T at 10-15ppm in mandarins.
At 10ppm and NAA at 20ppm have effectively prevented fruit drop in mango. Application of planofix
containing NAA at pea seed and marble size of the fruits completely controlled early fruit drop in
Guava.

Parthenocarpy: Partenocarpic fruit set could be induced in a no. of vegetables like cucurbits,
bhendi, brinjal, chillies and tomato and fruits like guava, straw berry, citrus, watermelon
etc.IAA,IBA,NAA,NOA,NAD,2,4-D,IPA and GA are effective in different plants. Application of GA at
100 ppm induced complete seedlessness in grape varieties Viz., Anab-e-shahi,Pachadraksha
etc.The problem of development of seeds in Poovan variety of Banana in Trichy area of Tamilnadu
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is controlled by application of 2,4-D at 25ppm in the bunches when the last hand is opened.

Fruit ripening: The plant growth regulators can be employed to hasten or delay fruit ripening. Plant
growth regulators like 2, 4, 5-T at concentrations of 25 to 100ppm has been found to hasten the
ripening in some varieties of plums and peaches. In banana ethrel treatment at 2500ppm induces
ripening in 24 hours.
Application of 2, 4-D at 16ppm delays ripening in Washington navel oranges. In Calymirna fig
maturity and ripening of the fruit is greatly hastened by spraying 2, 4, 5-T, while in apples in addition
to this B-Nine also hastens ripening by about 1-4 weeks. Ethephon has been shown to hasten
ripening in grapes.
In tomatoes all fruits on a plant won‘t mature and ripen at a time .This is a serious disadvantage for
mechanical harvesting .Ethephon applied 1-2 weeks before harvest promotes degreening and
ripening of tomatoes. Application of smoke is commercially employed to hasten and ripen bananas,
the active ingredient responsible being ethylene. Ethyphon is also employed for degreeing and
colour development of harvested fruits.

Fruit size and quality: Increase in berry size in Anab-e-shahi,Kismis and Bhokri varieties was
reported when GA was applied at 40ppm at bud and flower stages. Higher concentrations resulted
in the increase in the length of berries.

Sex expression: Plant regulators can be employed to modify the sex expression in crops. In
cucurbitaceous vegetables the production of male flowers will be always more in number than the
female flowers and this sex ratio can be narrowed down by the application of ethrel at 100 to
250ppm, if sprayed four times at weekly intervals commencing from 10 to 15 days after sowing. This
growth regulator not only increases the number of female flowers to male flowers, but also produces
female flowers at earlier nodes. Application of GA, the sex ratio is shifted towards maleness in
several cucurbits.

Certain plant regulators are employed to induce male sterility in crop plants, so that such male
sterile plants can be used as a female plant in the hybridization work. This process dispenses the
expensive work. Complete male sterility in bhendi can be obtained by spraying with 0.4% of MH. A
single spray one week before floral bud initiation offers male sterility for 10 days and a subsequent
spray at floral initiation extends the effect to 22 days.

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 Lecture 31: Water management –Irrigation - Methods of Irrigation- Surface Check basin, Furrow,
Ring Basin, Basin, Flood, Pitcher, Drip and Sprinkler irrigation system and their merits and demerits.

Irrigation:

It is defined as the artificial application of water to the crop plants in the event of
shortage of natural rains in order to obtain rapid growth and increased yields. It is essential
item in the cultivation of crops. Success in gardening depends on how efficiently irrigation's are
provided to gardens because it is governed by many factors such as frequency, duration, intensity,
source and method of supply.

Methods of Irrigation

Principally, irrigation systems can be divided under three broad headings:

1. Surface Irrigation: Supplying water to the soil without aerial application is known as surface
irrigation. It depends on gravity for spread of water over the area. This system generally use more
quantity of water.

a) Flooding

b) Basin type

c) Furrow type

d) Ring type

2. Sub-Surface Irrigation

a) Trench method

b) Through underground pipelines

c) Perforated pipelines.

3. Overhead or Aerial Irrigation

a) Sprinkler

b) Revolving Nozzles

 Drip or Trickle Irrigation

1. Surface irrigation:

a) Flooding

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 When the land is flat, letting in water from one end floods the entire area. This system is
commonly practiced in canal or tank bed areas. It is the easiest method and permits the use of
bullock drawn implements in the orchards. But in this there is wastage of water and leads to soil
erosion also. This is followed in wet lands mostly for banana. It encourages growth of weeds and
spread of diseases like gummosis in citrus and collar rot in papaya.

b) Basin System

In this system, circular basins are provided around the trunk of the tree. The basins are inter-
connected in series and are fed through the main channel running perpendicular to the tree rows.
When compared to flooding, this system minimizes the loss of water. In this system of irrigation, the
water close to trunk may bring about certain diseases like gummosis and nutrients are likely
to be carried over from one basin to the other.

c) Furrow system

Unlike the flood system, here the entire land surface is not covered with irrigation water. The
furrows are opened in the entire orchard at 4’ or less apart, depending upon the age of the trees.
Water is let in these furrows from the main channels.

In orchards, two furrows on each side of the rows are generally made. It is suited to such
lands, which have a moderate slope to the extent of 1-2% if the water is to run freely and reach
the ends of the furrows. Where the slope is sharp, the furrows are made to follow the contour more
or less closely. This method has disadvantage of excess of water penetration at the head than at the
farther end, which may result in variation in vigour and growth of trees. This is most widely followed
for vegetable crops like tomato, onion, brinjal etc.

d) Ring system

This is an improvement over the basin system. In this system, a ring is formed close and
around the tree and water is let into the basin. This method is recommended for citrus trees
thereby reducing the chances of collar rot to which these trees are often susceptible.

The size of the ring will increase as the tree grows .In this system, the spread of diseases like
collar rot, etc., are prevented. However, it involves more labour and capital and it does not permit
uniform distribution of water throughout the bed or basin as in the basin system of irrigation.

e) Bed
This is adopted in heavy soils for fruit crops like banana, wherein 3-4 plants are enclosed in
a bed and is irrigated by opening on one side of the bed.

2. Sub-Surface Irrigation

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 This system consists of conducting water in number of furrows or ditches underground
in perforated pipelines until sufficient water is taken into the soil so as to retain the water table near
the root zone.

In limited situation, this may be a very desirable system of irrigation. In general, however, it
must be used with great caution because of the danger of water logging and salt accumulation.
If the sub-strata are so slowly permeable that practically no water moves through, water added
may stand in soil sufficiently for long time resulting an injury to the plant root due to poor aeration.

Where irrigation water or the sub-soil contains appreciable amount of salt, sub-soil irrigation
is usually not advisable. Land must be carefully leveled for successful subsoil irrigation so that raising
the water table will wet all parts of the field equally.This method is costly and deep cultivation is not
possible. But, evaporation of moisture is prevented to a great extent.

3. Over-Head or Aerial Irrigation

In this system, water is applied in the form of spring, somewhat resembling rainfall. This
is accomplished by pumping water from original source into the main supply line from where it is
distributed to perforated pipes, which operate at low pressure (80 to 120 lb per square inch) and
supply the water in a fairly uniform rectangular pattern. They have a high rate of application, usually
1”/hour or higher. Because of the high application rates, their use is restricted to soils with high
infiltration rates, such as sandy or gravelly. Revolving nozzle is also at times used, which operated
on either low or high pressure. Usually the rate of application followed in the rate of 0.2” to 0.3” per
hour.

Sprinkler irrigation

May have definite economic advantages in developing new land that has never been irrigated,
particularly where the land is rough or the soil is too much porous, shallow or highly erodable.
It is quite useful where only small streams are available, such as irrigation wells of small capacity. It
is helpful in irrigating at the seedling stage when the furrowing is difficult and flooding leads to
crusting of soil. Fertilizer materials may be evenly applied by this method. This is usually done by
drawing liquid fertilizer solutions slowly into the pipe. It has several disadvantages like high initial
cost, difficult to work in windy location, trouble from clogging of nozzle, interference in pollination
process and requirement of more labours while removing or resetting. In general, this system is best
adopted for areas where ordinary surface systems are inefficient.

Drip or Trickle Irrigation System

This is the most recent system of irrigating the plants. It is usually practice for high value
crops, especially in green houses and glass houses. There will be an installation of pipelines with
nozzles very close to the soil. The nozzle is fitted in such a way that water is dripped almost in the
root-zone of the plants. Water is allowed to move in pipes under very low or no pressure and it drop
at regular interval. This system of irrigation has advantages like no disturbance of the soil; soil
moisture is maintained, lesser leaching of nutrients from the soil.
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Advantages

1. Water saving – water is applied directly to the root zone, eliminating wastage. 30 to 70
percent water saving
2. Labour saving – This is eliminates the need for constructing borders, bunds and labour
intensive works associated with conventional irrigation techniques, there by saving about
to 60to90%
3. Use of lower quality water – water is applied continuously and the root zone is kept wet
constantly.
4. Increased yield and plant vigor – It maintains soil moisture at optimum level eliminating
water stress resulting in greater vigour, better establishment and high productivity.
5. Reduced weed growth – Since water is applied to the restricted area, wide spread weed
growth is inhibited due to restricted water supply
6. Saving of nutrients – nutrients are directly applied to the root zone along with water.
Leaching losses are minimized. saving upto 30 to 60%

Disadvantages
1. Higher initial investment
2. Clogging of drippers due to oxidants, bi oxides and algae.

Pitcher system

 Pitcher with a hole at the bottom is buried in the tree basin where feeder roots are confined
(Figure 8.3).
 When it is filled with water, water is released slowly as droplets, which meet the water
requirement of plant.
 Number of pitcher per tree depends upon the spread of the tree. However, 4 to 5 pitchers per
tree are sufficient for the tree having 3 m spread.
 This system is highly a boon in the arid region where availability of water is limited.

Fertigation

Fertigation is a new technique of applying fertilizers particularly soluble fertilizers along with
irrigation water, through drip system. Optimum use of fertilizers, water

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 Lecture 32: Fertilizer application in Fruit Crops-Types of Fertilizers-Time of Fertilizer
application, Methods of Fertilizers application - Broad casting - advantages and
Disadvantages, Band placement, Ring Placement, Foliar application, Starter solutions,
Fertigation.

Fertilizer application in Fruit crops

The perennials are different from annuals in their nutritive requirements. The annuals require
fewer nutrients when gradually falls as the crop matures. Whereas, in perennials there are often
two or three peak period of uptake owing to the occurrence of more than one vegetative flush
and crop. Manurial requirement of perennials gradually increased with the age of the tree till the
trees reach their full growth and thereafter remains constant. Depending upon the requirements,
we may have to supplement by applying manures and fertilizers at the appropriate time.

Types of Fertilizers: 2 types

Inorganic fertilizers

 Industrially manufactured chemicals.

 Contains higher nutrient than organic manures.

 Nutrient input is lost through leaching, runoff, volatilization, fixation by soil or consumption
by weeds etc.

Organic fertilizers

 These are plant and animal wastes that are used as nutrients after decomposition.

 Improves the soil tilth, aeration, water holding capacity and activity of micro-organism.

Time of Fertilizer application:

It must be applied when the plants need it. Timing depends on the type of fertilizer
and climate. Fruit trees require more nutrients at the emergence of new flushes and
differentiations of floral buds. Utilized more during the course of fruit development.
Nutrients should be available to them in February–March. So, it would be better to apply
them in October-November to be available to the trees in February to March.

1. Nitrogen is required throughout the crop growth and all nitrogenous fertilizers are readily
soluble in water and loss is found to occur. So it is better to supply nitrogenous fertilizers
in split doses. ie.basal and top dressing.
2. Phosphorus is required in large amounts in the early stages of growth. All phosphatic
fertilizers are found to be slow acting and fixed in the soil and hence the entire quantity of
these fertilizers are applied as basal.
3. Potassium is required throughout the crop growth but the release of this nutrient is slow
and hence entire quantity is applied as basal dressing.

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 Methods of Fertilizer application

1. Broadcasting

 Fertilizer in solid state or granular or dust are spread uniformly over the entire field.
Leaching loss may be more.

Disadvantages

 Some of the elements like phosphorous and potash do not readily move in the soil.
Therefore, surface application may not be available to the trees especially in drier tracks.

 Leads to accumulation of potassium in surface soil beyond detrimental levels causing injury
to plants.

 Surface application always stimulates weed growth.

2. Band placement

 Application of fertilizer on the sides of rows.

 Fertilizer in solid and liquid forms can be applied.

 Quantity of fertilizer may be economized.

3. Ring Placement

 Commonly followed in fruit trees.

 Fertilizers are applied in a ring encircling the trunk of the trees extending the entire canopy.

 It is more labour intensive and costly.

4. Foliar Application

 Fertilizers are applied in liquid form as foliar sprays.

 They are easily absorbed by leaves.

 Fertilizers are applied in a very low concentration tolerable to the leaves.

 Recommended when the nutrients are required in small quantity.

 Eg. Urea spray in brinjal and bhendi

Starter Solution

 Liquid form of fertilizer application.

 Seedlings and propagules are kept emerged up to their root system for varying duration in
starter solution.

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 The starter solution is prepared either by dissolving concentrated fertilizer mixture at a
concentration not exceeding 1%.

5. Fertigation

 Application of fertilizers in irrigation water in either open or closed systems.

 Nitrogen and sulphur are the principal nutrients applied.

 Phosphorous fertigation is less common because of formation of precipitates takes

place with high Ca and Mg containing water.

Advantages

 Nutrients especially nitrogen can be applied in several split doses at the time of greatest
need of the plant.

 Nutrient is mixed with water and applied directly near the root zone, as such higher use
efficiency.

 Cost on labour is saved.

Best results of fertigation are noticed when the fertilizer is applied towards the middle
of the irrigation period and their application terminated shortly before completion of
irrigation. Use of soluble fertilizer improves use efficiency.

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