Sheath rot caused by Sarocladium oryzae (Sawada) W. Gams and Hawksw,considered a minor disease till a few years ago, has attained status of amajor disease. It is primarily because of the introduction of the some ofthe high yielding varieties. It might increase further with the popularizationof the hybrid varieties. Typical symptoms are oblong to irregularbrown to gray lesions on boot leaf sheath near panicle. Lesions maycoalesce covering the entire sheath. Disease is highly damaging as itinfects boot leaf sheath (Figures 1B & 3) and under severe condition itmay totally inhibit panicle emergence. Burning of the infected stables,planting of the tolerant varieties, spray of fungicide like carbendazim(Table 1) at tillering and boot leaf stage (Swain et al., 1997) and biocontrolagent are some of the methods recommended for the disease management.A wide variation was observed in natural incidence of sheath rot indifferent germplasms/land races of Indian aromatic rices (U. S. Singh,R. K. Singh and G. S. Khush, personal observation). Early planted ricecrops could escape disease incidence (Swain et al., 1997).
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