09-08-2013, 04:55 PM
Management of powdery mildew of wheat and assessment of avoidable losses
ABSTRACT
Powdery mildew of wheat (Triticum aestivum L.) is a foliar disease caused by the obligate biotrophic fungus Blumeria graminis DC f. sp. tritici Em. Marchal (syn. Erysiphe graminis DC f. sp. Tritici Marchal) is a disease of major importance. This disease causes yield loss every year in many wheat producing regions. Application of foliar fungicides has traditionally been the only means of chemical control for powdery mildew.
The field trials were conducted for two consecutive years during 2009-10 and 2010-11, at Chatha farm, SKUAST-Jammu. The experiments were laid out on a susceptible wheat variety, PBW-343 in Randomized Block Design with seven treatments including control (One spray of Tilt 35 EC @ 0.1 %, Two spray of Tilt 35EC @ 0.1%, One spray of Bavistin 50@ 0.1 %, Two spray of Bavistin 50% @ 0.1%, Three spray of Sulfex @ 0.3%, Two spray of Karathane @ 0.05% and Control (No spray). Two spray of Tilt 25 EC (0.1%) (Ist spray at initiation of disease and 2nd spray after 15 days) were found best, followed by its one spray at initiation of disease. Mean disease score was found to be reduced to minimum level of 0.27 as compared to control (6.99). Bavistin was also enhanced the yield but Karathane and Sulfex were found more superior to increase the yield than Bavistin. Per cent decrease increase avoidable yield loss was maximum (30.59%) with 2 spray of Tilt 25 EC @ 0.1% as compared to control. The other fungicides also controlled the disease and enhanced the yield levels in comparison to the control.