Symptoms
- Yellowing of the entire network of veins in the leaf blade is the characteristic symptom.
- In severe infections the younger leaves turn yellow, become reduced in size and the plant is highly stunted.
- The veins of the leaves will be cleared by the virus and intervenal area becomes completely yellow or white.
- In a field, most of the plants may be diseased and the infection may start at any stage of plant growth.
- Infection restricts flowering and fruits, if formed, may be smaller and harder.
- The affected plants produce fruits with yellow or white colour and they are not fit for marketing.
- The virus is spread by whitefly.
Management
- Spray azadirachtin 0.03 WSP @ 5 g/10l or methyl demeton 25 EC @ 1.6 ml/l or thiamethoxam 25 WG @ 2 g/lit to kill the insect vector, whitefly.
- By selecting varieties resistant to yellow vein mosaic like Parbhani Kranti, Arka Abhay, Arka Anamika, and Varsha Uphar, the incidence of the disease can be minimised.
- The virus is transmitted by the whitely ( Bemisia tabaci, .
- Parbhani Kranti, Janardhan, Haritha, Arka Anamika and Arka Abhay can tolerate yellow vein mosaic.
- For sowing during the summer season, when the whitefly activity is high, the susceptible varieties should be avoided.
- Synthetic pyrethroids should not be used because it will aggravate the situation.
- It can be controlled by application of Chlorpyriphos 2.5 ml + neem oil 2 ml lit of water.