Identification of Brown Spot Disease in Cultivated Rice Field of Uttar Pradesh

Abstract

Brown spots were observed throughout the growing season and may vary in size, shape and color depending on the environmental conditions, age of the spots and the degree of susceptibility of the rice variety. Disease development was favored by high relative humidity (86-100%) and temperatures between 24-30°C. So, rice plants were cultivated using standard agronomic practices becouse circular to oval spots emarginated during the maturity in rice leaves. The spotted leaves in rice were associated with weak plants growing under stressful conditions such as water stress, inadequate fertilization and herbicide toxicity. The disease was measurement with, Area Under Brown Spot Progress Curve (AUBSPC). Under laboratory conditions, six fungicides (propiconazole, hexaconazole, tricyclazole, carbendazim, triadimefon and mancozeb) were tested. Out of different fungicides, propiconazole was most effective with maximum inhibition of 96% at 250 ppm concentration. Under field conditions, six rice varieties viz. Sarju-52,Medium- 3022,MTU-7029,HUBR-2-1,BPT, Malviya Basmati-105, were used for testing different fungicides at 0.1% concentration during Kharif Season-2015 and application of propiconazole significantly reduced the disease severity and increased the grain yield of all the varieties as compared to their respective controls. It was concluded that timely spray of propiconazole reduce the disease severity and thereby increase the yield of the rice.