Diseases of Custard apple

1. Siddu Lakshmi Prasanna
Course No.: PATH 2.7.1.
Course Title: Diseases of Fruit, Plantation, Medicinal
and Aromatic crops
By
Dr. Siddu Lakshmi Prasanna
Ph. D (Agri.)
Dept. of Plant Pathology

2. Custard apple
Sr. No. Disease Causal organism
1. Anthracnose Colletotrichum
gloeosporioides
2. Glomerella fruit rot Glomerella cingulata
3. Leaf spot Cylindocladium colhounii
4. Diplodia rot Botryodiplodia theobromae
5. Black canker Phomopsis annonacearum
6. Spiral nematode and
Stunt nematode
Helicotylenchus sp.
Tylenchorhynchus claytoni
Scientific name: Annona squamosa
Siddu Lakshmi Prasanna

3. Anthracnose/Fruit Rot
Causal organism: Colletotrichum gloeosporioides
Telomorph: Glomerella cingulata
SYMPTOMS:
Leaves: Dark margin with greyish center and as disease progresses the center
region falls off and dirty greyish colour indicates the presence of acervulus.
•Infection begins at blossom-end of the fruit and later spreads on entire fruit
surface, affected fruits shrivel and they may cling to the tree or fall
down.
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4. •Necrotic spots of 2-10 mm in diameter appear on unripe fruits which
turn into dark brown to black spots. These spots coalesce later and cover
entire fruit.
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5. Epidemiology:
•Wet and windy conditions favors the disease
•Temperature 28-32° C
Primary source of inoculum: Older fruits left on the trees provide inoculum
for disease spread. Conidia present in infected plant debris
Secondary source of inoculum: air borne conidia
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6. Disease cycle
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7. Management:
Cultural methods:
• Use mulching under the trees to reduce soil splash.
• Remove dead twigs and mummified fruits.
• Prune the trees 50cm above ground.
• Avoid planting susceptible varieties.
Chemical methods:
• Spray carbendazim@0.1% or chlorothalonil@0.2%
Siddu Lakshmi Prasanna