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.