CHEMICAL MANAGEMENT OF BACTERIAL LEAF BLIGHT DISEASE IN RICE

Abstract

Bacterial leaf blight (BLB) is an economically important disease of rice caused by Xanthomonas oryzae pv. oryzae. Use of chemicals is an important part of plant disease management. For this purpose, comparative efficacy of three antibiotics, Flare 72 WP (streptomycin sulphate), Cordate 4 WP (kasugamycin) and Castle 50 WP (kasugamycin+ copper oxychloride) alongwith four fungicides, viz. Copper oxychloride 50 WP (copper oxychloride), Nativo 75 WDG (Tebuconazole+trifloxystrobin), Gem Star Super 325 SC (azoxystrobin+difenconazole) and Bordeaux mixture, was studied as foliar spray applications against Xanthomonas oryzae pv. oryzae. The experiment was conducted under natural environmental field conditions at farmer’s field, Faisalabad during two years (2012-2013). Super Basmati variety of rice, susceptible to the pathogen, was grown in the field. Among the tested chemicals, Flare 72 WP performed as the best with 92.23% disease control and increase in rice yield upto 3.55% over the untreated control. Castle 50 WP gave disease control upto 87.97% with an increase in yield by 3.01%, Cordate 4 WP gave 86.31% control with increase in yield of 2.90% among fungicides, Copper oxychloride 50 WP gave disease control of 76.48% with 2.67% rice yield increase, Nativo 75 WDG gave disease control of 68.63% with 1.30% increase in yield, Gem Star Super 325 SC showed 63.67% disease control and yielded 0.47% more over untreated control treatment . Bordeaux mixture treatment gave disease control upto 84.08% with 2.78% rice yield increase over untreated control. Mean disease incidence in the untreated control treatment remained as 85.67%. In general, all the treatments significantly reduced incidence of disease and improved rice yield higher than untreated control during the study period.