Cotton seedlings are subject to attack by several fungal and bacterial diseases. These include the anthracnose fungus (C. gossypii), Ascochyta blight (A. gossypii), wilt fungus (F. o. f.sp. vasinfectum), bacterial blight (X. a. pv. malvacearum), Pythium spp. and Rhizoctonia solani.
Pythium spp. are particularly serious where soil temperatures are low and wet weather prevails at planting.
Rhizoctonia solani causes sore shin disease of cotton seedlings. Attacked seedlings develop dark to reddish-brown cankers on the stems near the soil line. The cankers encircle the stems or penetrate so deeply that the plants fall over and die.
- Use disease-free seeds.
- Avoid planting during cold, wet weather.