Agriculture and Forestry University
CNRM, Sindhuli
A Post-Harvest Pathology
U Mr. Ganesh Lamsal
Assistant Professor
ganeshlamsal@afu.edu.np
9845440209
PLANT DISEASE
• “Any deviation from normal functioning of the
physiological process, of sufficient duration to cause
disturbance or cessation of vital activity”
A
F • Pathological
– caused by living, parasitic
U microorganisms
• Physiological
– caused by abiotic factors
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Disease Triangle - Factors impacting on
microbial dynamics
Preharvest level Postharvest level
Macro & Micro:
Temperature
Environment Macro & Micro:
A Rainfall patterns
Temperature
Wind Gas levels
UV
F Other Microbes:
RH
Interactions
Natural
Intrinsic factors
U Virulence
antagonists
Physiological fitness
Surface features:
Physiological fitness Inherent level of resistance Wax type/ structure
Age/ time after harvest Exudates
Population genetic variation
Stress levels
Pathogen/s Host Korsten, 2007
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
TYPES OF INFECTION OF DISEASES
1. OUTRIGHTLY VISIBLE DISEASE BEFROE HARVEST
Usually the pathogens micro-organisms are abundant in plant
debris, soil and environment
During rain or wind, these propagating structures are
A transported to the fruits and the plant organs
When they get free water, start germinate and produce lesions,
F canker, scab and necrotic spots
PREHARVEST INFECTION
U
SOOTY MOLD
SCAB CANKER
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
TYPES OF INFECTION OF DISEASES
2. LATENT INFECTION
The development of diseases occurs when the environment is
suitable i.e. when the fruit is ripe Eg. Crown rot in banana
U
ANTHRACNOSE BOTRYTIS ROT
Infection is incurred before harvest but symptoms become apparent at the
end of the chain
LATENT OR QUIESCENT INFECTION
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Latent Infection
Banana: Crown Rot = Colletotrichum musae
Mango: Anthracnose = C. gloesporoides
A Apple: lenticel Rot = Cryptosporious curispora
Citrus: Stem End Rot = Phompsis citri
F Diplodia natalensis
Alternaria citri
U
Papaya: Anthracnose =C. gloesporoides
Peach: Brown Rot =Monilinia fructicola
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
A
Apple: lenticel Rot = Cryptosporious curispora
Mango: Anthracnose = C. gloesporoides
F
Papaya: Anthracnose=C. gloesporoides
Citrus: Stem End Rot= Phompsis citri
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
TYPES OF INFECTION OF DISEASES
3. INFECTION DURING OR AFTER HARVET
Some injuries and wounds are created during harvesting and
subsequent handling.
A wound or scratch may be invisible to open eyes but it can be
A avenue for the entry of micro-organisms.
STRICTLY POSTHARVEST
F
U
PENICILLIUM ROT
SOUR ROT
COTTONY LEAK
By: Mr. Ganesh Lamsal (Assistant professor)
BLACK ROT
Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Infection During or After Harvest
Apple: Blue mold rot = Botrytis cinerea
Citrus: Blue mold = Penicilluim expansum
Green mold = P. diditatum
Peach: Rhizopusm rot = Rhizopus stolonifera
A
Banana: Crown rot = Colletotrichum musae
F Fusarium roseum
Verticillium theobromae
U Thielaviopsis paradoxa
Pineapple: Black rot = Thielaciopsis paradoxa
Vegetable: bacterial Soft Rot =Erwina carotovora
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
MAJOR POSTHARVEST DISEASES
ANTHRACNOSE
U Symptoms
Circular sunken spots with pink
spore masses apparent during
humid conditions
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
STEM END ROT Green mold
CROWN ROT P. digitatum
YEASTY ROT
Stem end rot Blue mold
Lasiodiplodia theobromae Sour rot Penicillium italicum
By: Mr. Ganesh Lamsal (Assistant professor)
Geotrichum candidum
BACTERIAL SOFT ROT
(Pectobacterium carotovorum sub sp. carotovorum)
By: Mr. Ganesh Lamsal (Assistant professor)
POSTHARVEST DISEASE CONTROL
PRINCIPLES INVOLVED
Identify the causal agent of the
disease
A Thorough knowledge of the
following:
F Biology of the pathogen and the
disease cycle
Relationship between disease
U development and the environment
Cultural management practices
Postharvest handling operations
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
POSTHARVEST DISEASE CONTROL: STRATEGIES
Control of pre-harvest infection
Pre-harvest fungicide management
A (Benomyl spray at 14 days interval
for Anthracnose of mango)
F
Field hygiene and sanitation
U Bagging
Use of resistant cultivars
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Control of infection during and after harvest
Sanitation / cleanliness
- sterilize storage room with 300 ppm chlorine
A - fumigate storage room with formaldehyde (2:1)
- treat wash tanks and containers with 6-8% borax or 0.25%
F hypochlorite solution
Careful handling (Reduce injuries)
U Avoid favorable conditions for
microbial development
Culling of infected fruit
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Chemical treatments
wraps soaked with fungicides (biphenyl)
Fumigants: SO2 – release pads (grapes)
Acetic acid (5%) vapor (strawberries)
Fungicides application
A Chemical Group Brand Name Crop Disease Rate
Prochloraz Sportak mango anthracnose 55mL 100L-1
F Benomyl Benlate
(restricted) mango anthracnose 200g100L-1
Carbendazim Bavistin mango anthracnose 100mL 100L-1
U Thiophanate
methyl Topsin-M banana anthracnose 2-4g L-1
Thiabendazole Tecto F banana anthracnose 2mL L-1
Fosetyl Aliette 80 durian Phytophthora 4g L-1
Aluminum rot
Use of fungicides after harvest is limited because of the problem of residues
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Biological Control
Manipulation of the host through induced systemic resistance
A Direct or indirect use of antagonistic
microorganisms
F - Bacteria: Bacillus subtilis; Pseudomonas syringae
- Fungi: Penicillium funiculosum; Trichoderma viridae
U
- Yeasts: Picchia guillermondi; Candida oleophila
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
Physical method: Heat Treatments
Benefits from HWT
Hot Water Dip
Leaves no chemical
residue
Mango (‘Carabao’)
52-55ºC, 5-10 min
Removes latex stains if
Papaya (‘Solo)
applied within 24-36 hours
after harvest
49-51ºC, 10 min
Banana
Enhances uniform fruit 45ºC, 20 min
ripening Hot water brush (Israel)
Mango
By: Mr. Ganesh Lamsal (Assistant professor) 61-62ºC, 20 sec
Delaying of symptom appearance
- regulation of ripening
low temperature storage
atmosphere modification (retards microorganism growth)
Growth regulators, antisenescent chemicals = GA; 2,4 – D
(Alterinaria citri)
Irradiation
Homoeopathic drugs (Lycopodium-140 in mango against Pestalotia
mangiferae)
By: Mr. Ganesh Lamsal (Assistant professor)
By: Mr. Ganesh Lamsal (Assistant professor)
A
F Thank You
U
n-gl.com
By: Mr. Ganesh Lamsal (Assistant professor) Post-harvest horticulture, BSc Ag., 6th semester CNRM, Sindhuli, Agriculture and Forestry University
