Cercospora leaf spot
Caused by: Cercospora gossypinaProblem Category: Fungal Disease
Symptoms: Circular red lesions on leaves which enlarge and turn white or gray in the center; lesions often have a pattern of concentric rings and possess a red margin; dark gray spore masses form in the centers of the lesions making them appear dark gray.
Comments: Fungus overwinters in crop debris from previous growing season; commonly found alongside Alternaria leaf spot and other foliar disease.
Management: Plow crop residue into the soil to reduce inoculum levels; provide plants with adequate irrigation and nutrients; applications of appropriate foliar fungicides may be required on susceptible cultivars.
Control: spray 5% cowurine + Asafoetida solution to control cercospora leaf spot