K. BASAVANA, GOUDABDUL RAHAMAN, M. NADAF2019-05-202019-05-202007-08-29TH8652http://krishikosh.egranth.ac.in/handle/1/5810104005Investigations were carried out during 2004-05 and 2005-06 at college of Agriculture Dharwad, on the survey of pink bollworm infestation, reaction of Bt and non-Bt cottons, infestation in Bt and non-Bt cotton, comparative development of pink bollworm on Bt and non-Bt cotton bolls and molecular characterization of pink bollworm. The pink bollworm infestation at different locations surveyed was significantly less in Bt cotton compared to non-Bt cotton. The maximum larval population, green boll damage and locule damage was recorded at Raicbur in Bt cotton (5.44 larvae/50 bolls, 9.45% and 16.06%, respectively) and non-Bt cotton (10.75 larvae/50 bolls, 20.62% and 26.31%, respectively). Across the locations, Bt cotton recorded more GOBs per plant (18.47 to 21.07) and less BOBs per plant (4.05 to 4.98) and more seed cotton yield (8.8 to 9.97 q/ba)ennullThesis