Evaluation of ipm modules against whitefly bemisia tabaci (Gennadius) in cotton

On-farm trials were conducted for the evaluation of IPM modules in cotton against the whitefly Bemisia tabaci (Gennadius) by the Krishi Vigyan Kendra, Bathinda and Mansa at five locations during 201718 and 2018-19. The modules included neem-based insecticides along with detergent powder, darek (Melia azedarach L.) extract and the University recommended insecticides compared with that of farmers’ practice of mixing of non-recommended insecticides. The data revealed significantly maximum reduction (80.0- 85.1% and 80.9- 85.4%) in the incidence of adults compared to the University recommended practice (Mj) at Bathinda and Mansa, respectively. This was followed by module (Mj) comprising use of home-made darek extract (54.4 to 63.3% at Bathinda and 58.0 to 72.5% at Mansa). Module (M₃) comprising of addition of detergent powder in neem-based spray solution remained on a par with M with 55.8 to 62.7 and 57.4 to 71.9% reduction in incidence over untreated check. Farmers’ practice of spraying non-recommended insecticides resulted in minimum reduction in incidence (16.7 to 23.1% and 23.6 to 36.3%, at Bathinda and Mansa, respectively). The trend in yield was similar to the above, with maximum being in M₄ followed by Mj and M₃ with the least yield being with the module comprising of use of non-recommended sprays by the farmers. Maximum number of spray applications (5-6) were given in M₄ (farmer’s practice). Maximum and minimum B: C ratio was obtained with the modules M₄ (1.3 to 1.5) and M₄ (0.8 to 1.2), respectively.