Cassava Tuber Rot, (Phytophthora palmivora) – An Emerging Threat to Cassava Production

Cassava, Manihot esculenta, is a perennial shrub in the family Euphorbiaceae grown primarily for its storage roots which are eaten as a vegetable. Tuber rot of cassava is a serious problem in Tamil Nadu. The disease is primarily caused by Phytophthora palmivora, and many secondary invaders also get associated with the disease at later stage. Phytophthora root rot is prevalent in waterlogged soils. The disease causes yield losses up to 80% and severe incidence was recorded in black soils, where the cassava was grown frequently. Biocontrol agents (Trichoderma viride) were very effective in reducing fungal growth of the disease.