Field Screening of Cabbage and Cauliflower Genotypes for Resistance to Pieris brassicae and Plutella xylostella under Field Conditions

Field screening was conducted to evaluate fourteen cabbage and fourteen cauliflower genotypes for resistance to Pieris brassicae and Plutella xylostella under natural field conditions at the Vegetable Experimental Farm, SKUAST-K, Shalimar, during Kharif 2024. The experiment was arranged in a randomised complete block design with three replications. Larval population and plant infestation were recorded at fortnightly intervals from 15 days after transplanting until harvest, and genotypes were classified using defined resistance categories. For P. brassicae, larval population ranged from 0.66 to 14.06 larvae plant⁻¹ in cabbage and from 0.53 to 9.06 larvae plant⁻¹ in cauliflower, while plant infestation ranged from 6.00 to 66.00 per cent in both crops. For P. xylostella, larval population ranged from 0.07 to 4.53 larvae plant⁻¹ in cabbage and from 0.07 to 3.80 larvae plant⁻¹ in cauliflower, with infestation ranging from 6.00 to 80.00 per cent and from 6.00 to 73.00 per cent, respectively. Four genotypes in each crop were classified as resistant to P. brassicae, while four cabbage and four cauliflower genotypes were also classified as resistant to P. xylostella. The screening demonstrated substantial genotypic variation in pest response. The resistant and moderately resistant materials identified in this study provide candidates for further multi-environment validation and potential use in resistance breeding and integrated pest management.