ACHARYA N.G.
RANGA AGRICULTURAL UNIVERSITY
Advanced Post Graduate Centre, Lam, Guntur
COURSE NO : AGRON 504
COURSE TITLE: Principles and Practices of Water management
TOPIC : Fertigation, fertigation approaches and fertigation
scheduling
Submitted to
Dr. S. Bharathi
Professor and Head
Department of Agronomy
Submitted by
Bhuvaneswari. K
GAM/24-02
1
FERTIGATION, FERTIGATION APPROACHES AND FERTIGATION
SCHEDULING
INTRODUCTION:
Productivity of crops is based on effective utilisation of water and fertilizers (nutrients)
along with other inputs. Provision of optimum quantity of water and fertilizer in most cost -
efficient manner is the challenge facing the farmer for profitable farming. The answer to the
challenge is fertigation, where both water and fertilizers are delivered to crops simultaneously
through a micro irrigation system.
Application of fertilizers through irrigation system is referred to as fertigation.
Fertigation = Fertilizer + Irrigation water, Fertilizers and water are delivered simultaneously
through the irrigation system in precise combination and timing.
Fertigation has a potential to supply a right mixture of water and nutrients to the root zone, thus
meeting plants water and nutrient requirements in most efficient possible manner (Patel and
Rajput, 2001).
Fertigation allows the crop to use up to 90 percent of the applied nutrients.
Fertigation ensures saving in fertilizer (40-60 percent), due to better fertilizer use efficiency
and reduction in leaching (Kumar and Singh, 2002).
Incorporation of soluble fertilizers into irrigation water facilitated the integration and
harmonization between the application of water and plant nutrients. Using fertigation an
adequate supply of nutrients and water can be directed towards the plant root zone to satisfy
plant daily various growth stages.
Daily application rate of nutrients through fertigation is changing during the growing
season and is planned to follow plant daily demand according to its nutrients uptake pattern.
Fertigation in any irrigation system, requires the injection of soluble fertilizer solutions into the
irrigation water by dosing devices- injectors. High quality, fully water-soluble fertilizers are
required for the preparation of appropriate nutrient solutions.
2
It has become an attractive method of fertilization in modern intensive agriculture. This
has assumed additional importance after the introduction pf micro- irrigation system like drip
irrigated agriculture.
ADVANTAGES OF FERTIGATION
1. Higher nutrient use efficiency: Nutrient use efficiency by crops is greater under
fertigation compared to conventional application of fertilizers to the soil.
2. Higher resource conservation: Fertigation helps in saving of water, nutrients, energy,
labor and time.
3. Efficient delivery of micronutrients: Fertigation provides opportunity for efficient use
of compound and ready-mix nutrient solutions containing small concentrations of
micronutrients, which are otherwise very difficult to apply accurately to the soil when
applied alone.
4. Healthy crop growth: When fertigation is applied through the drip irrigation system,
crop foliage can be kept dry thus avoiding leaf burn and delaying the development of
plant pathogens.
5. Helps in weed management: Fertigation helps to reduce weed menace particularly
between the crop rows. Use of plastic mulch along with fertigation
through drip system allows effective weed control in widely spaced crops.
6. More flexibility in farm operations: Fertigation provides flexibility in field operations
e.g. nutrients can be applied to the soil when crop or soil conditions would prohibit
entry into the field with conventional equipment.
7. Less water pollution: Intensification of agriculture led by the use of irrigation water
and indiscriminate use of fertilizers has led to the pollution of surface and ground water
bodies by chemical nutrients. Fertigation helps lessen pollution of water bodies through
the leaching of nutrients such as N and K out of agricultural fields.
DISADVANTAGES OF FERTIGATION
1. Uneven distribution of nutrient occurs when there are faults in the irrigation system.
This can lead to nutrient leaking when excess water is applied to crops.
3
2. Wastage of fertilizers due to leaking can lead to soil and water pollution. This can
damage flora and fauna.
3. Some micronutrients and phosphatic fertilizers may precipitate in micro-irrigation
systems.
4. Risk of chemical reaction of fertilizers. For instance, Ca and Mg react with fertilizers
and form bicarbonates in the water. This leads to severe chemical clogging.
5. There are chances of chemical backflow into the water supply.
METHODS OF FERTIGATION/ FERTIGATION APPROACHES
Four systems are generally used:
1. Continuous application: Fertilizer is applied at a constant rate from irrigation start to
finish. Total amount is injected regardless of water discharge rate.
2. Three stage application: Irrigation starts without fertilizers. Injection begins when the
ground is wet. Injection cuts out before the irrigation cycle is completed. Remainder of
the irrigation cycle allows the fertilizer to be flushed out of the system.
3. Proportional application: The injection rate is proportional to the water discharge rate,
e.g., 1l of solution to 1000 l of irrigation water. Fertilizer recommendation can also be
expressed in terms of kg/ha/day (or week). This method has the advantage of being
extremely simple and allows for increased fertigation during periods of high-water
demand when moist most nutrients required.
4. Quantitative application: Nutrient solution is applied in calculated amount to each
irrigation block, e.g., 20 l to block A, 40 l to block B. it can also be expressed in terms
of concentration (g m3 = ppm). This method is suited to automation and allows the
placement of the nutrients to be accurately controlled.
FERTIGATION SCHEDULING
Factors that affect fertigation schedules are soil type, available NPK status, organic
carbon, soil pH, soil moisture at field capacity, available water capacity range, aggregate size
4
and distribution, crop type and its physiological growth stages, discharge variation and
uniformity coefficient of installed drip irrigation system. Efficient fertigation schedule neds the
following considerations:
• Crop and site-specific nutrient management
• Frequent nutrient delivery to meet the crop needs
• Controlling irrigation to minimise leaching of soluble nutrient below effective root zone
• Nutrient can be injected daily or bimonthly depending upon system design, soil type
and farmer’s preference.
In many situations, a small percentage of N and K (20-30%) and most or all P is applied in pre-
plant broadcast or banded application especially in the areas where either initial soil levels are
low or early season irrigation is not required. Pre-plant application of P is common since
soluble P sources (phosphoric acid) are costlier than granular forms, to avoid chemical
precipitation in drip line. Movement of drip applied P away from the injection point is governed
by soil texture and soil pH. Movement of P is restricted in the fine textured and alkaline soils.
When making a pre-plant application of any nutrient, it is important that the fertilizer be placed
with in the wet zone of the drip system.
Fertilizer should be injected in a period such that enough time remains to permit
complete flushing of the system without over irrigation. Water that moves below the active
crop root zone carry nitrate N or K in substantial quantities. One cm of each of leach rate at
100 mg nitrate N/ litre would contain 10 kg N/ha.
EXAMPLE FERTIGATION SCHEDULE
Table. 1: Fertigation schedule for seasonal (12 months) ratoon sugarcane:
Nutrients (kg/ha/day)
Days after planting
N P2O5 K2O
Jan-30 1.2 0.1 0.2
31-80 1.5 0.4 0.24
81-110 2 1 0.4
111-150 0.75 0.3 0.75
151-190 1.5
5
CASE STUDY- 1: Nutrient and water use by Bt. Cotton (Gossypium hirsutum) under drip
fertigation
-D. D Pawar et al.
-Indian Journal of Agronomy 58(2): 237-242
A field experiment was conducted for three consecutive summer seasons from 2008 to 2010 at
research farm of Mahatma Phule Krishi Vidyapeeth, Rahuri.
MATERIALS AND METHODS:
• The field experiment was laid out with eight treatments replicated thrice in randomized
block design (RBD).
• The treatments comprised three fertigation schedules - A, B and C
Table- 2: Fertigation schedules for cotton
• The schedules A (T4) and C (T8) are being used by farmers in some part of the state for
cotton cultivation presently; whereas, schedule B was developed on the basis of nutrient
requirement of crop during different growth stages.
• In schedule B, three levels, 75% (T5), 100% (T6) and 125% (T7) of recommended dose
(120:60:60, NPK kg/ha) were incorporated as fertigation. The fertigation treatments
were compared with conventional irrigation method (T1), only drip (T2) and only ‘N’
fertigation (T3). The nutrients in kg/ha were applied in equal weekly splits as per three
schedules.
• Under drip irrigation, Bt. cotton ‘Rashi-2’ was sown using 0.75–1.50 × 0.75 m paired
row planting. Two rows of cotton were dibbled at 0.75 m spacing and one row was
skipped over after that; thus, maintaining 0.75 m distance between two rows and 1.50
m between two pairs.
• Plant to plant spacing of 0.75 m was kept along the row. One 16 mm in–line lateral with
drippers at 0.60 m spacing was laid for each pair. It maintained the lateral-lateral
spacing of 2.25 m.
• The fertigation was done using automized fertizet system (Haleon, Israel) at weekly
interval as per schedule. Water soluble fertilizers viz. Urea (46:0:0) NPK grade
(18:18:18) and sulphate of potash (0:0:50) were used for fertigation in treatments T4 to
T8. In control treatment (T1 to T3), conventional fertilizers urea, super phosphate and
muriate of potash were used.
6
RESULTS AND DISCUSSIONS:
Yield and yield attributes:
• Application of 125% recommended dose of water-soluble fertilizers (WSF) through
schedule B recorded significantly higher number of bolls/plant (116.37) followed by
treatments T6 and T8 where 100% WSF were applied using schedule B and C,
respectively. The conventional method (T1) produced minimum number of bolls/plant
(70.69).
Table-3: Yield contributing characters, cotton yield and water use of cotton as influenced
by water soluble fertilizers (Pooled data of three years)
Water Use
• Water use Maximum mean water use including effective rainfall was observed in
conventional method of irrigation (743.90 mm).
• The drip irrigated treatments used only 320.10 mm during whole season, indicating that
drip irrigation can save water to the extent of 56.9% as compared to the conventional
irrigation.
• Water use efficiency was comparatively higher in 125% drip fertigation schedule B
(14.22 kg/ha–mm) as compared to other treatments.
• It was followed by 100% fertigation schedule B (13.20 kg/ ha–mm), 100% fertigation
schedule C (13.15 kg/ha–mm) and 75% fertigation schedule B (12.23 kg/ha–mm). This
is in confirmation with the findings of Ramamurthy et al. (2009) that drip can increase
the cotton yield in addition to water saving.
• The minimum water use efficiency of 3.74 kg/ha–mm was obtained in conventional
method of irrigation.
7
CASE STUDY- 2: Effect of drip irrigation, fertigation and plastic mulching on growth
and yield of soybean (Glycine max)
-Angrej Singh and K. G. Singh
-Indian Journal of Agronomy 66(1): 56-60
A field experiment was conducted during the rainy season of (kharif) 2017 and 2018 at
Ludhiana, Punjab, to study the effect of drip irrigation, fertigation and plastic mulching on
productivity and quality of soybean [Glycine max (L.) Merr.].
MATERIALS AND METHODS:
Of the 12 treatments T1 to T9 were sown after laying plastic mulch under bed planting system.
The treatment details are:
➢ T1, drip irrigation at 0.6 × Etc with 50% RDF through fertigation;
➢ T2, drip irrigation at 0.6 × Etc with 75% RDF through fertigation;
➢ T3, drip irrigation at 0.6 × Etc with 100% RDF through fertigation;
➢ T4, drip irrigation at 0.8 × Etc with 50% RDF through fertigation;
➢ T5, drip irrigation at 0.8 × Etc with 75% RDF through fertigation;
➢ T6, drip irrigation at 0.8 × Etc with 100% RDF through fertigation;
➢ T7, drip irrigation at 1.0 × Etc with 50% RDF through fertigation;
➢ T8, Drip irrigation at 1.0 × Etc with 75% RDF through fertigation;
➢ T9, drip irrigation at 1.0 × Etc with 100% RDF through fertigation.
➢ T10, drip irrigation at 1.0 × Etc with 100 % RDF through fertigation with no mulch;
T11, drip irrigation at 1.0 × Etc with 100% RDF through fertigation + paddy straw
mulch and
➢ T12, furrow irrigation with 100% RDF as conventional broadcast application (basal
application).
The recommended dose of fertilizer (RDF=100%) comprised 10 t/ha FYM, 31.25 kg N and 60
kg P2 O5 /ha.
In the control plot with bed/furrow method of irrigation and manual application of fertilizer by
broadcasting before sowing was considered as conventional/ control treatment (T12).
The soybean variety ‘SL 958’ was sown on 15 and 11 June 2017 and 2018 respectively.
Drip irrigation in different, treatments were given on every 3rd day (except rainy days) for
whole season using 16 mm laterals with inline drippers and operated at a pressure of 1.5
kg/cm2.
Daily ET values for the crop sea son were calculated using Modified Penman method based on
daily meteorological data collected from the PAU, Ludhiana.
8
Fertigation was done, starting from 15 days after sowing (DAS), total fertilizer was applied in
8 equal splits at weekly interval up to 75 days after sowing (DAS).
RESULTS AND DISCUSSIONS:
Table. 4: Growth, yield attributes and seed yield of soybean as influenced by irrigation,
fertigation and mulching (pooled data of 2 years)
Growth parameters:
The data on plant height at maturity showed that under plastic mulch treatments (T1-T9) the
maximum plant height was recorded under T9 which was statistically at par with T6, T8 and
T11.
Yield attributes:
The maximum number of pods per plant was recorded under T9 treatment, being statistically
at par with T6 and T8 treatments and significantly higher number of pods/plant than all the
other treatments.
Table. 5: Protein content, oil content and oil yield of soybean as influenced by irrigation,
fertigation and mulching (pooled data of 2 years)
9
Quality parameters:
The maximum protein content was recorded under T11which was statistically at par with T6,
T8, T9 and T10 and significantly higher than all the other treatments.
CASE STUDY- 3: Effect of drip irrigation and fertigation on the performance of several
rice cultivars in different rice ecosystems in India
- Soman et al. 2018
- International Journal of Agriculture Sciences 10(14): 6672-6675.
MATERIALS AND METHODS:
The demonstration trials were carried out in farmers’ field in seven States
1. Andra Pradesh (AP) covering Vizag, Kadapa, Kurnool, East Godavari and
Vijayanagaram districts
2. Telangana covering Medak, Karimnagar, Nalgonda districts
3. Chhattisgarh, Durg district
4. Rajasthan, Kota district
5. Punjab Patiala, and Ludhiana districts
6. Tamil Nadu Cuddalore, Tiruvannamalai, Madurai districts, and
7. Maharashtra, Raigarh district
During 2009 to 2014, monsoon or “Kharif” June-July sowing, as also Winter or “Rabi” Oct-
December sowing was done.
Direct seeded rice (DSR) and also seedling transplanted rice crops were raised. The
cultivars/genotypes used were tried earlier by the respective farmers under low land rice
system.
The field was, dry ploughed, harrowed, levelled, irrigated to germinate weeds, again ploughed
back, harrowed, raised beds of 15 cm height and 120 cm wide were formed. A basal dose of 25
t of organic cattle manure, 345 kg SSP, 25 kg each of zinc sulphate and ferrous sulphate per ha
were incorporated.
Two laterals of 16 mm with 4 lph drippers at 50 cm spacing along the drip line are placed at 40
cm interval in each bed. In case of direct sowing, (DSR) pre-germinated seeds, two in each
hole at 20 cmX15 cm were dibbled at two cm depth. In case of transplanted crop, seedlings
from the nursery were transplanted on to the wet beds irrigated by drip. Irrigation was applied
as per the schedule.
10
Table. 6: Irrigation schedule for drip method
Mean daily Crop water
S. No Period evaporation (mm/ requirement
day) (l/ha/day)
st
1 June 1 FN 5.53 12289
nd
2 June 2 FN 5.53 55300
st
3 July 1 FN 5.42 60222
nd
4 July 2 FN 5.35 59444
st
5 Aug 1 FN 5.23 69733
nd
6 Aug 2 FN 4.91 65466
st
7 Sept 1 FN 4.87 54111
The quantum of irrigation varied from location to location based on the evapotranspiration (ET)
and the season of the crop. Fertilizers were injected through a ventury system.
The fertigation schedule indicating the nutrients supplied at different stages of growth and
quantities of recommended dose of nutrients applied.
The fertilizers in water soluble form in splits applied through drip at a frequency of two
occasions per week to mitigate the high pH of the soil.
Weeds were controlled by application of pendimethalin at 1.25 l/ha after 3 days sowing, plus
manual weeding at critical stage of growth 45 days after sowing.
Routine observation for stem borer and leaf roller were made and appropriate treatment given.
The conventional flood system plot was prepared by puddling, seedlings transplanted and the
same rate of fertilizers was applied in four splits. Other practices were according to
conventional system.
Observations on yield and yield components recorded, yield per ha calculated, percentage
increase/ decrease over control (conventional low land puddled, flood system) calculated.
Besides these observations on all the farms, four individual farmers were selected for detailed
study, one each from Punjab, Rajasthan, Chhattisgarh, and Andhra Pradesh; cost of inputs
including amortized cost of drip system, total and net returns, Benefit: Cost ratio etc. were
calculated.
Table. 7: Fertilizer recommendations for each state (basis for fertigation)
Fertilizer NPK
State of India N P K
Andhra Pradesh & Telangana 180 62.5 75
Chhattisgarh 220 55 125
Maharashtra 100 50 50
Punjab 150 60 45
Tamil Nadu 150 50 50
11
RESULTS AND DISCUSIONS:
- In drip irrigated and fertigated farms, the performance, in terms of grain yield varied
between 5.928 t- and 11.61 t/ha showing wide variation in yield, amongst the fifteen
genotypes used; and was maximum 11.61 t/ha from genotype JGL 1798, in Madurai,
Tamil Nadu, during monsoon (Kharif) 2013 with direct seeded crop.
- This was followed by hybrid ADT-45 yielding 9.63 t/ha, during Rabi, 2012, direct
seeded crop, from Tiruvannamalai, TN. The hybrids US-311, MTU 4870 ranked third
in respect of yield, recording 9.386 t/ha during kharif, 2009, direct seeded, in Medak,
Telangana and Kadapa, AP respectively.
- The results have explicitly demonstrated that drip irrigation and fertigation technology
with appropriate proportion of nutrient fertilizers in dissolved form when injected in
irrigation water at twice a week interval had resulted in maximum fertilizer-use-
efficiency and optimum yield response and saving in water (not measured in the present
studies) and recorded enhanced yield in drip irrigated farms from 17.2 to 29.9 % over
the flood irrigated fields, thus establishing the efficacy of drip irrigation and fertigation
technology in increasing the yield of grains over conventional flood irrigated system.
- While the agronomists and extension scientists of Jain Irrigation have taken efforts to
popularize using drip irrigation and fertigation technology amongst the rice farmers in
the country, using latest extension methods, the challenges remain viz.
- Generally, the farmers’ response to new technologies is slow, even when there is yield
advantage. As the majority of farmers are small/marginal (holding
- Considering that millions of hectares of rice are cultivated using conventional, puddled,
flood system, and the huge water saving, yield advantage and ease in cultivation
involved in using drip system, the government and the farmers should jointly make
efforts to spread the area under such water saving technologies so as to avert impending
water crisis in the country.
CASE STUDY- 4: Drip fertigation effects on yield, nutrient uptake and soil fertility of Bt
Cotton in semi-arid tropics.
- Jayakumar et al.
- International Journal of Plant Production 8(3): 1735-6814
Field experiment was conducted for 2 seasons to study the influence of drip fertigation in
combination with or without bio fertilizers on yield, plant uptake and soil fertility of Bt cotton.
MATERIALS AND METHODS:
The experiment was laid out with a set of ten treatments in randomized block design with three
replications. Intraspecific cotton hybrid NCS 145 Bt (Bunny Bt) released from Nuziveedu
seeds limited, Hyderabad was used as the test variety.
The treatments are
- T1 Drip fertigation with 75 per cent RDF of NPK
12
- T2 Drip fertigation with 75 per cent RDF of NPK and biofertigation of azophosmet
- T3 Drip fertigation with 100 per cent RDF of NPK T4 Drip fertigation with 100 per
cent RDF of NPK and biofertigation of azophosmet
- T5 Drip fertigation with 125 per cent RDF of NPK
- T6 Drip fertigation with 125 per cent RDF of NPK and biofertigation of azophosmet
- T7 Drip fertigation with 150 per cent RDF of NPK
- T8 Drip fertigation with 150 per cent RDF of NPK and biofertigation of azophosmet
- T9 Drip irrigation and soil application of 100 percent RDF of NPK
- T10 Surface irrigation and soil application of 100 per cent RDF of NPK as control
Yield attributes viz., number of sympodial branches per plant, number of fruiting points, bolls
per plant and boll weight of Bt cotton were recorded by adopting standard procedures.
The seed cotton obtained from each harvest was weighed and yield of five pickings were
accumulated and expressed in kg/ ha.
RESULTS AND DISCUSSIONS:
Yield components:
Adoption of drip fertigation with 150 per cent recommended NPK and biofertigation
(T8) recorded higher number of sympodial branches (18.1), fruiting points (68.5), number of
bolls (29.5) and boll weight (4.8 g/ boll) than the other treatments.
Seed yield:
Drip fertigation with 150 per cent recommended dose of NPK and biofertigation (T8)
recorded the highest seed yield of 3395 kg/ ha. However, fertigation at 150 per cent
recommended NPK with and without biofertilizer and application of 125 per cent NPK with
biofertigation of azophosmet produced comparable yield and were superior over the rest of the
treatments.
Nutrient uptake:
Effect of drip fertigation on nutrient uptake
13
Drip fertigation with 150 per cent recommended dose of NPK and biofertigation (T8)
was significantly superior with the highest N, P and K uptake of 110.9, 28.2 and 110.6 kg ha-1
at 120 DAS, respectively.
CASE STUDY- 5: Drip fertigation significantly increased crop yield, water productivity
and nitrogen use efficiency with respect to traditional irrigation and fertilization
practices: A meta-analysis in China
- Li et al. 2021
- Agricultural Water Management. 244, 106534
MATERIALS AND METHODS:
• Boosted regression tree (BRT) models were used to quantitatively evaluate the
relative effect of the variables (crop type, soil texture, MAP, MAT, N application rate
and irrigation amount) on the crop yield, ET, WP and NUE responses.
• Meta-analysis is a formal quantitative statistical method to summarize results from
independent experimental studies (Hedges et al., 1999). In this study, they used the
effect size (R) to quantify the effect of drip fertigation treatments on crop yield, ET,
WP and NUE.
RESULTS AND DISCUSSIONS:
Crop yield response-
Overall, drip fertigation significantly increased crop yields by 12.0% (with a 95% confidence
interval of 10.0–14.1%) compared to farmers’ practices.
Fig: The effect of drip fertigation vs. farmers’ practices on crop yield
14
The effect sizes of drip fertigation on yield were significantly different among all the studied
crops (P< 0.05) potato showed the highest increase in yield (40.3%), followed by fruit (13.7%),
maize (12.7%), cotton (11.7%), vegetable (9.7%), tobacco (7.6%) and wheat (6.0%).
Water productivity response:
- In general, drip fertigation significantly enhanced WP by 26.4% (with a 95% confidence
interval of 20.9–32.7%) and decreased ET by 11.3% (15.6% to 6.8%) compared to farmers’
practices.
- The increase in WP by drip fertigation was highest in the semiarid region (60.7%), followed by
the arid region (51.8%) and semi- humid region (22.3%).
- Compared to farmers’ practices, drip fertigation significantly increased WP by 18.8 34.8% and
decreased ET by 10.3–19.7% under different N application rate situations but the amplitude of
the effect on WP and ET by drip fertigation was independent of the N application rate (P > 0.05)
- In the rainfed farming system, drip fertigation showed a positive effect on both ET
(16.9%) and WP (18.0%).
Nutrient use efficiency responsive:
- On average, drip fertigation increased NUE by 34.3% (with a 95% confidence interval
of 29.0–40.1%) compared with farmers’ practices. Among all studied crops, fruit
showed the highest increase in NUE (68.2%), followed by potato (46.0%), legume
(41.7%), vegetable (33.1%), maize (22.6%), wheat (18.2%), tobacco (17.1%) and
cotton (16.5%).
- NUE responses to drip fertigation were significantly positive in fine (51.7%), medium
(33.7%) and coarse (30.7%) textured soils.
- Drip fertigation generally had positive effects on NUE regardless of the irrigation
amounts, and the highest increase was observed when the irrigation amount was lower
than the farmers’ practices (34.9%), however, the magnitude did not depend on the
irrigation amount (P > 0.05).
References:
Pawar, D., D., Dingre, S., K., Bhakre, B., D and Surve, U., S. 2013. Nutrient and water use by
Bt. cotton (Gossypium hirsutum) under drip fertigation. Indian Journal of Agronomy.
58(2): 237-242.
Singh, A and Singh, K., G. 2021. Effect of drip irrigation, fertigation and plastic mulching on
growth and yield of soybean (Glycine max). Indian Journal of Agronomy. 66(1): 56-60.
Li, H., Mei, X., Wang, J., Huang, F., Hao, H and Li, B. 2021. Drip fertigation significantly
increased crop yield, water productivity and nitrogen use efficiency with respect to
traditional irrigation and fertilization practices: A meta-analysis in China. Agricultural
Water Management. 244, 106534.
Soman P., Prasad, M., S., Balasubramaniam, V., R., Sarwan, S., Dhavarajan, C., Patil, V., B and
Sanjeev, J. 2018. Effect of Drip Irrigation and Fertigation on the Performance of Several
15
Rice Cultivars in Different Rice Ecosystems in India. International Journal of
Agriculture Sciences. 10(14), 6672- 6675.
Jayakumar, M., Surendran, U and Manickasundaram, P. 2014. Drip fertigation effects on yield,
nutrient uptake and soil fertility of Bt Cotton in semi arid tropics. International Journal
of Plant Production. 8(3). 375- 390.
16
