Downy mildew

Early stages of the disease are characterised by indefinite yellowish-green areas on the upper surface of the leaves. As the disease progresses, those infected areas become greyish brown or dark brown and have yellowish-green margins. Severely infected leaves fall off prematurely. A greyish mould-like growth develops on the under surface of the spots when weather is wet and temperatures are cool. The disease also attacks the pods and infects the seeds. The disease is favoured by cool temperatures and wet conditions.