“It affects leaves, stems and tubers.Water soaked spots appear on leaves, increase in size, turn purple brown& finally black colour White growth develops on under surface of leaves.This spreads to petioles, rachis& stems. It frequently develops at nodes.Stem breaks at these points and the plant topples over. In tubers, purplish brown spots and spread to the entire surface on cutting, the affected tuber show rusty brown necrosis spreading from surface to the center.”