Target spot
Caused by: Corynespora cassiicolaProblem Category: Fungal Disease
Symptoms: The symptoms can be found on leaves, boll bracts and on bolls. Initially the appearance of small chocolate brown spots which later enlarge to become circular to irregular spot with target markings. The symptoms are mainly seen in the lower canopy. Typically the infected leaves retain their green color or green yellow color. Under severe conditions leaf and flower drop may occur.
Comments: The pathogen also infects cucumber, sweet potato, soybean and tomato. It will cause severe loss if pathogen infect at flowering stage. The disease is common in Southeastern cotton producing states of USA. The target spot is confused with leaf spot caused by Cercospora spp. Stemphyllium spp. or Alternaria spp. But this spot is surrounded by reddish to purplish margin.
Management: Use available resistant varieties. Follow crop rotation. Spray sour buttermilk
Control: spray 5% cowurine +Asafoetida solution to control Target spot