Measures to Control Bacterial leaf spot in Chilli Crop

9 February 2024

Bacterial leaf spot (BLS) is a common and destructive disease of chilli. especially under favorable conditions. It is caused by bacteria that enter the plant through natural openings or wounds in the leaves. Once inside, the bacteria multiply and spread, causing the leaves to wilt, turn brown, and die.

Bacterial Leaf Spot in Chilli

Type of Infestation: Bacterial Disease
Common Name: Bacterial leaf spot
Causal Organism: Xanthomonas campestris pv. vesicatoria
Affected Parts Of the plant: Leaves

Environmental favorable factors for pests/Diseases:

Temperature: The bacterium thrives in warm temperatures, with optimal growth occurring between 25-30°C (77-86°F).
Humidity: Moist conditions, including frequent rain, fog, or overhead irrigation, promote bacterial growth and spread. Relative humidity above 85% is ideal for infection.

Symptoms of Pest/Disease:

Small, water-soaked spots on the leaves, which may enlarge and turn brown or black
Yellow halos around the spots
The spots may become raised or scabby
Leaves may wilt, curl, or drop prematurely
In some cases, the fruit may also be affected, developing spots, blemishes, or even rotting.

Measures to control Pests/Diseases:

Products	Technical Names	Dosages
KTM	Thiophanate Methyl 70% WP	250-600gm/Acre
Coc50	Copper oxychloride 50 % wp	2gm/ltr
KMYCIN	Sulphate	6-12 gm in 60 L water

Frequently Asked Questions:

Q. What is bacterial leaf spot of chilli?

A. It is a bacterial disease on chilli leaves that causes wilting and death of the leaves.

Q. What are the symptoms of Bacterial Leaf Spot?

A. Water-soaked spots on leaves that later turn brown or black, and wilting of leaves.

Q. Which products are effective for controlling Bacterial Leaf Spot?

A. Products like KTM, Coc50, and KMYCIN are effective.

Q. How often should treatment be applied for Bacterial Leaf Spot?

A. It depends on the weather and severity of infection, but generally, 2-3 applications are needed.

Q. What is the temperature for Bacterial Leaf Spot?

A. Warm temperatures (25-30°C) and high humidity (above 85%) are ideal for bacterial growth.

Q. What is the causal organism of bacterial leaf spot in chilli?

A. Bacterial leaf spot (BLS) in chilli is caused by multiple Xanthomonas biotypes, primarily Xanthomonas euvesicatoria pv. euvesicatoria.

For more information about pests and diseases, read our other blogs.