author(s)
Roomi Rawal, KK Dahiya and Adesh Kumar

abstract
The present experiment was carried out on seven varieties of cotton under unsprayed condition. Experiment was carried out at research farm of cotton section, Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar. Bollworms infestation was recorded at 90, 120 and 140 days after sowing and finally at harvest. At 90, 120 and 140 days after sowing significantly higher boll damage was observed on non-Bt variety H-1236 and minimum was recorded in BIOSEED-6588 and it was superior over all other genotypes. And at harvest time damage was recorded in open bolls and locule basis. Highest infestation in open bolls and locule basis was recorded in non-Bt genotype H-1236 and lowest was found in Bt genotype Bioseed-6588 that was (28.63%), (6.70%), (1.27%) and (0.40%) respectively. Yield was recorded highest in Bt genotypes as compared to non-Bt genotypes.