Peanut bud necrosis

Peanut bud necrosis is a destructive viral disease caused by the Peanut bud necrosis orthotospovirus (PBNV). This virus primarily impacts legumes and vegetables, causing significant economic losses in global agriculture due to reduced yield and poor crop quality.

The transmission of the virus is exclusively mediated by thrips, particularly Thrips palmi. The virus is acquired during the larval stage of the insect, and once acquired, the thrips remains infectious for its entire adult lifespan. Environmental factors like high temperatures and low rainfall often favor the rapid multiplication of vector populations.

The host range for PBNV is extensive. In addition to groundnuts (peanuts), it infects a wide variety of crops including tomatoes, bell peppers, potatoes, and various leguminous species. Many common weeds act as asymptomatic reservoirs, ensuring the survival of the virus in the field throughout the year.

The most common symptoms include chlorotic spots, mosaic patterns, and ring-like necrotic markings on leaves. Infected plants show stunted growth, shortened internodes, and the death of terminal buds, which prevents normal flower development and pod setting. In severe cases, the entire plant may wither and die.

Management strategies focus on reducing the population of the vector and minimizing viral spread. Key practices include:

• Planting early to avoid high pest pressure periods.
• Using intercropping with tall barrier crops to disrupt thrips movement.
• Implementing weed control to eliminate virus reservoirs.
• Applying targeted insecticides to manage thrips during early growth stages.