Alternaria leaf blightCaused by: Alternaria helianthi
Problem Category: Fungal Disease
Symptoms: Dark brown lesions on leaves surrounded by a yellow halo; lesions coalesce and become irregularly shaped and cause leaves to become blighted; plant becomes defoliated and dies
Comments: Disease emergence favors hot weather and frequent rainfall; fungus may survive in crop debris or on suitable weed hosts; disease can be transmitted through infested seed
Management: Prune out infected leaves; use adequate plant spacing to reduce humidity around plants and promote good air circulation; disease can be controlled by application of appropriate foliar fungicide
Control: spray 2 times 10% Cowdung+Asafoetida solution in 10 days interval.