Brinjal

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Post harvest diseases of brinjal
Anthracnose Colletotrichum melongenae
Fruit rot
Phomopsis vexans
Alternaria solani
Pythium aphanidermatum
Phytophthora nicotianae var
nicotianae
Fruit rot - Phomopsis vexans

First phase - blight on young seedlings

Stem - girdled slightly above the soil line, plant topples and
dies

Stem lesion - dark brown, becoming grey in the centre as
pycnidia develops

Leaf - irregular brown spots

Fruits – soft, watery & decays

Finally black, mummified as pycnidia develop abundantly
over the surface
Fungus
 Pycnidia - with or without beak, brown to black

Conidiophores - hyaline, simple or branched, Conidia from pycnidium

Conidia - hyaline, one celled and subcylindrical

Stylophores - filiform, curved, hyaline, septate
Mode of spread and survival
 Seed borne

Spread by rain splashes, implements and insects

Survives in infected plant debris in soil
Epidemiology
 Temp - 29oC (fungal growth)

Storage rot of fruits is maximum at 25oC
Management
 Seed treatment - hot water @ 50oC for 30 min

Nursery - 0.2 % difolatan or captan 0.2% @ weekly interval

Field - Zineb 0.2 %
Bordeaux mixture 0.8%
Fruit rot - Alternaria solani

Small, concentric dark brown & sunken spots

Spots coalesces & covers entire fruit
Fungus
 Hyphae - septate, branched, light brown becoming darker with
age

Conidia - single, muriform, beaked and dark in color

Source of infection - infected seeds and plant debris

Pusa purple - moderately resistant
Alternaria solani conidia. Note the transverse
and vertical septa and the long "beak
Favourable conditions
 Temp - 25 to 30oC
 Sporulation – abundant when rains are frequent and heavy
Mode of survival and spread
 Conidia and mycelium in the soil and debris - remain viable for
> 17 months
 Conidia are windborne
Control
 Spraying of zineb 0.2 % or mancozeb 0.2%
Fruit rot - Pythium aphanidermatum

Referred as cottony leak

Decay begins at blossom end

Purple colour of the skin bleaches and turns to tan and wrinkling
follows

Fleshy tissue becomes watery

White cottony mycelium of the fungus covers the surface
Fungus

Mycelium - coenocytic, white and measures 2.8 - 7.5 μm in dia

Produce sporangia, zoospores, and oospores

Oogonia - spherical, smooth walled, terminal on lateral hyphae
Mode of spread and survival
 Survival: Through oospores present in the soil
 Spread: Through irrigation water, implement during cultural
operations
Favourable conditions
 Excessive soil moisture
 High humidity
 Over crowding of seedling
Control

Remove affected plants and burn
Avoid water logging condition
Drench the soil with 1% Bordeaux mixture

Fruits should not be allowed to touch the soil

Do not store the infected fruits with healthy fruits


Fruit rot - Phytophthora nicotianae var nicotianae

Fruits - Small, water soaked lesions

Skin - discoloration, turns greyish brown, and develop white
cottony mycelium in humid weather

Rotten parts become depressed and develops wrinkles

Rotting spread deep into the pulp and turns brown, watery &
soft
Rapidly spreads during rainy season

Fungus
 Hyphae - 5 to 6 μm in dia
 Spherical hyphal swellings are common
 Zoosporangia - sub hyaline, oviod, pyriform borne on short
stalk
A: Sporangia. B: Zoospore. C:Chlamydospore.
D: Oospore.
Control
 Removal and destruction of the affected fruits

Spraying the crop with Difolatan (0.3%) thrice at an interval of
10 days effectively controls the disease
Anthracnose - Colletotrichum melongenae

Sunken lesions on fruits vary in size

Upto 1.3cm wide and may coalesce

Tan colored ooze of fungal spores appear on lesions

Fruit dries & become black – fruit drop
Fungus
 Mycelium - septate, branched & light pink to brown
 Acervuli - simple globose and dark brown
 Conidiophore - erect and hyaline
 Conidia - hyaline, one celled, oval or oblong
Mode of spread and survival
 Survives on crop debris as acervuli
 Spores dispersed by rain splash
Epidemiology
 RH - 100%
 Temp - 21 to29oC
Control
 Field sanitation - destruction of infected plant debris
 Other host plant - S. torvum
 Harvesting of fruits before they over ripe
 Zineb or ferbam spray at 10 days interval
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