Bud necrosis

Symptoms:

• Chlorotic spots or rings on young leaflets
• Necrosis of terminal bud

Identification of pathogen:

Favourable Conditions:

• Temperature: 30ºC
• Wind speed: 10 km/h favour migration of thrips

Mode of Spread and Survival:

• Thrips palmi and other species transmits GBNV in circulative and propagative manner
• The virus survives on ornamentals ( Zinnia , cosmos and sunflower), weeds ( Ageratum conyzoides , Cassia tora , Acanthospermum hispidum , Desmodium triflorum ) and crop plants (tomato, brinjal, green gram, black gram, beans, pea etc)

Management:

• Remove infected plants up to 6 weeks of sowing and spray systemic insecticide 30 days after sowing
• Antiviral principles (AVP) from sorghum or coconut leaves are extracted as follows to use: Sorghum or coconut leaves are collected, dried, cut into small bits and powdered. To one kg of leaf powder, two litres of water is added and heated to 60°C for one hour, filtered through muslin cloth and diluted to 10 litres and sprayed
• Spray any one of the following insecticides at fifteen days interval: imidacloprid 17.8 SL 125ml/ ha, quinalphos 25 EC @ 1400 ml/ha, quinalphos 1.5 DP @ 25 kg/ha