RICE :: FUNGAL DISEASES :: FALSE SMUT

False smut - Ustilaginoidea virens(Syn: Claviceps oryzae - sativa)
Symptoms
The fungus transforms individual ovaries / grains into greenish spore balls of velvetty appearance. Only a few spikelets in a panicle are affected.

Pathogen

Chlamydospores are formed as spore balls which are spherical to elliptical, warty and olivaceous.

Disease Cycle
            Grasses and wild rice species are alternate hosts. The main source of inoculum is air-borne spores. Ascospores produced from sclerotia act as primary source of infection while chalmydospores are secondary source of infection. Chlamydospores are air - borne, abundant at heading stage.
Favorable conditions

• Rainfall and cloudy weather during flowering and maturity