SUGARCANE CYTOSPORA SHEATH ROT IN IRAN

摘要

SHEATH rot symptoms were observed on commercial sugarcane varieties in Khuzestan province in south-west of Iran in 2001-2002. Koch's postulate was conducted to determine the causal agent. Symptomatic plants were collected and fungal organisms were isolated. In greenhouse grown plants, disease symptoms were reproduced in young shoots by inserting a fungal mycelium disk near the crown. Brick-red patches were observed on the outside and inside of the sheath 4-7 days after inoculation. Distinct pycnidiadeveloped on the surface of leaves three weeks after inoculation, and the leaves were rather rough due to numerous pycnidia. The infected leaves finally died. The fungus was re-isolated from the lesions and the pathogen was identified as Cytospora sacchari E.J. Butler, the causal organism of sheath rot. This is the first report of sheath rot of sugarcane caused by Cytospora sacchari from Iran.