Anamorph: Rhizoctonia solani f. sp. sasakii
(Teleomorph: Corticium sasakii, syn. Thanatephorus cucumeris)

Nature of damage

• The main damage is a brownish rotting of the ears.
• These show conspicuous, light brown, cottony mycelium with small, round, black sclerotia.

Signs

• True to the name, this disease develops on leaves and sheaths.
• Symptoms are characteristic concentric spots that cover large areas of infected leaves and husks.

Factors favoring development

• Humid conditions and irrigated fields are highly favorable for the disease.
• Additionally, high crop densities impact disease severity.

Geographical distribution

• Devastating epidemics of BSLB have been reported from Bhutan, China, India, Indonesia, Nepal, the Philippines, and Vietnam.
• Additionally, the disease has been reported in several African and Latin American countries.
• Generally the disease is most prevalent and severe in Asian countries where rice is intensively cultivated.