HomeInternational Rice Research Notesvol. 28 no. 2 (2003)

First Report of Narrow Brown Leaf Spot Disease of Rice in West Bengal, India

A. Biswas

Discipline: Biology, Agriculture



During the 2001 wet season (Jun - Nov), the popular, high-yielding, and widely adapted cultivar Swarna was observed to have many linear red-brown spots. These had light-colored margins and light brown to gray centers. Observed on leaves during the later (dough and mature grain) growth stages, the spots were restricted between the veins. The experimental plots of the  ricewheat system of the Rice Research Station, Chinsurah, were exposed to these weather conditions: mean maximum temperature, 32°C; mean minimum temperature, 25°C; relative humidity, 98%; and rainfall, 942 mm. A similar type of lesions was also found on the leaf sheaths, pedicels, and glumes. The lesions were 2–10 x 0.5–1 mm and they coalesced to form long, threadlike brown lesions parallel to the veins on the entire leaves.