• Increase font size
  • Default font size
  • Decrease font size
The Disease:  SHEATH ROT
Sarocladium oryzae (Sawada) (Gams and Hawksworth 1975)

Etymology: from Greek saron, broom; klados, branch.
Sheath rot occurs in all rice-growing countries. It causes significant yield loss during rainy season in both rainfed and upland ecosystems. Chen (1957) reported losses up to 85% in Taiwan. In India, Chakravorty and Biswas (1978) noted that sheath rot reduced yields of some varieties by 9.6 - 26.0%. Kang and Rattan (1983) reported losses up to 50% in Punjab.
Sheath rot appears on the uppermost leaf sheath which encloses the emerging panicle. Sheath rot lesions are irregular, 0.5 - 1.5 cm long, and have grayish centers and brownish margins. Sometimes the whole lesion appears gray-brown. In infected tillers, panicles emerge partially or not at all. Inside the sheath, a whitish powdery mass of fungus can be seen. Grains discolor brown. In the tropics, it is easily confused with sheath discoloration (caused by many Pseudomonas pathogens).
sarocladium oryzae habit sheath rot
Last Updated on Wednesday, 15 April 2009 07:26