Effect of Agro-Met Conditions on the Progression of Brown Leaf Spot Disease in Basmati-370 Rice

Abstract

Basmati-370 rice variety was used for the present investigation that has a distinct flavor and aroma, along with fine quality and moderately resistant to brown leaf spots. The primary emphasis of the research had been on the impact of climatic variables on brown leaf spot disease progression. The infection was initially identified in the late vegetative stage of each cropping season, viz., 2019 and 2020, and reached its peak during the maturity phase. In Kharif, 2018 the maximum infection rate (r) was observed during43rdMSW, whereas, in 2019 maximum infection rate (r) was observed during 39th MSW. The relation betweenweather factors and disease severity during 2018 designated a significantly negative correlation of -0.928and -0.903 with maximum and minimum temperature, respectively. Relative humidity (morning) had asignificant positive correlation (0.640), but relative humidity (evening), rainfall, and sunlight hours exhibitednon-significant negative correlations of -0.505, -0.418, and -0.362, respectively. In 2019, a substantial negativeassociation was found between illness severity and meteorological conditions. A significantly negativecorrelation of -0.917 and -0.937 with maximum and minimum temperature respectively, was observed.During the kharif, 2019 until the end of agricultural seasons, correlation study of disease progression withrelative humidity (morning), relative humidity (evening), sunlight (hr), and rainfall revealed non-significantand negative correlations.

Morpho-Cultural Variability Characterization of Bipolaris oryzae Causing Brown Leaf Spot of Rice in Jammu Sub-Tropics

“…The disease has spread throughout the world's rice-growing regions. It has been discovered to be pandemic in locations with high rainfall, such as the Assam, West Bengal, the Malabar Coast and Himalayas [5]. The pathogen attacks the crop from seedling to milky stage.…”

“…A relative humidity of >89% at 25°C leads to successful inoculation by conidia and infection can be vigorous upon free water on leaf surface [5]. Diversity and pathogenicity of the rice brown spot pathogen were investigated earlier by many researchers using morpho-cultural characteristics as well as genetic fingerprint analysis [7,8,9,10,11].…”