Measures to Control Late Blight in tomato

Learn effective measures to control late blight in tomato crops, including early detection, resistant varieties, and targeted fungicide application to protect your harvest from this devastating disease.

What is Late Blight Disease in Tomatoes?

Late blight, also known as potato blight, is a destructive disease that primarily affects potatoes and tomatoes. It is caused by the water mold Phytophthora infestans, and is known for its devastating impact on potato crops, particularly during the Irish Potato Famine of the 1840s.

Classification of Late Blight Disease in Tomato

Favorable factors for Late Blight in Tomato :

• Temperature: The optimal temperature range for late blight development is between 15 and 20°C (59-68°F). Temperatures outside this range can still allow for infection,
• Humidity: Late blight thrives in humid environments, with relative humidity above 80% being ideal. This is because high humidity promotes the formation and dispersal of spores, the reproductive units of the fungus.

Symptoms of Disease Late Blight in Tomato:

• Leaves: The first signs are usually small, water-soaked areas on older leaves that enlarge to form brown, oily-looking blotches.
• Stems: Brown lesions may develop on stems, causing wilting and dieback.
• Fruit: Brown, firm spots appear on the fruit, often starting at the shoulders. Infected fruit may eventually develop secondary rots.

Initial Symptoms of Late Blight in Tomato:

• Small, wet-looking spots appear on the leaves, usually starting at the edges.
• These spots quickly grow larger and turn dark brown or purple, with a yellow ring around them.
• A white mold may appear on the underside of the leaves, especially when it's humid.
• Dark, oily-looking spots may also show up on the stems.

Severe Symptoms of Late Blight in Tomato:

• The leaves get badly damaged, causing the plant to wilt and lose its leaves.
• Large, dark brown to black patches appear on the stems, which can cause the plant to collapse.
• Tomatoes develop dark, hard spots that grow bigger and often lead to the fruit rotting.
• The affected tomatoes may look oily and start to smell bad as they decay quickly.

Measures to control Late Blight in Tomato:

The Late Blight in Tomato can be managed by different control measures such as cultural control,biological control and chemical control.

Cultural control measures for Late Blight in Tomato:

• Adapt crop rotation with non-susceptible crops.
• Remove and destroy infected plant debris from previous crops.
• Provide adequate spacing between plants to improve air circulation and reduce humidity.

Biological Control measures for Late Blight in Tomato:

• Use biocontrol agents like Trichoderma spp. or other beneficial fungi that can help suppress Phytophthora.

Chemical control measures for Late Blight in Tomato:

FAQS related to disease Late Blight in Tomato:

Q What are the symptoms of late blight?

A. The symptoms of late Blight in Tomato are water-soaked black spots on the leaves and stems.These spots can grow fast, turning the whole leaf brown and dead. A white, mold-like growth may appear on the leaves, especially in damp conditions.

Q. How do you control late blight in tomatoes?

A. Late Blight in Tomatoes can be controlled by cultural, biological and chemical methods. For effective management all three control measures should be used.

Q. What causes late blight in tomatoes?

A. Late blight in tomatoes is caused by a pathogen called Phytophthora infestans, a type of water mold. This pathogen grows in cool, wet conditions and can spread rapidly, leading to severe damage to tomato plants.

Q. What is the best fungicide for Late Blight in Tomatoes?

A. The best fungicide for Late Blight in Tomatoes are Katyayani Professor and Katyayani COC 50.