Bacterial wilt
A soil-borne bacterial disease that causes sudden wilting of green plants, especially tomato, brinjal and chilli.
Also known as: Ralstonia wilt, Southern wilt
Symptoms and identification
Plants wilt suddenly during the hottest part of the day while leaves stay green, then fail to recover. A cut stem placed in a glass of clear water releases milky white streams of bacteria within minutes.
Causes
Ralstonia solanacearum lives in soil and water and enters through root wounds. Hot, wet weather and poorly drained soil favour it.
Organic treatment
Remove and destroy infected plants immediately with their soil. Do not compost them. Apply bleaching powder to the planting hole and avoid susceptible crops there for two to three years.
Prevention
Use clean potting mix for containers, rotate crops with non-solanaceous plants, improve drainage and avoid damaging roots.
Chemical treatment (use with care)
No reliable chemical cure exists; prevention and resistant varieties are the main control.