Incidence of spot blotch of wheat in Eastern Uttar Pradesh

Abstract

Bipolaris sorokiniana was mainly responsible for causing spot blotch of wheat in Eastern Uttar Pradesh. The disease appeared 5 to 8 weeks after wheat sowing and the symptoms advanced after heading stage and spreaded very fast. The dark brown necrotic spots (boat shaped) occured on the leaves, crowns and stems with or without yellow halo around these. Lesions on the leaves in the begging were few mm in size and extended as elongated dark brown spots and later on coalesced resulting into blight. In severe cases, at flowering stage 60 to 80 per cent leaf areas was turned into necrotic lesions. Intensity of spotting increased with the increase in the age of plants and reached maximum between boot to maturity stage of the crop. Minute spots were also observed on leaf sheaths, nodes, internodes and the glumes. Survey of five districts were conducted in Eastern Uttar Pradesh, clearly indicate that dominant pathogen responsible for causing spot blotch of wheat is Bipolaris sorokiniana because nearly eighty per cent of sample yielded Bipolaris sorokiniana in both the years. Maximum Bipolaris sorokiniana was recorded in Jaunpur 27&23 in the years of 2018-2019 respectively and minium B. sorokiniana was recorded in 9&6 in Faizabad districts in the years of 2019-2020 respectively.