Identification of Brassica oleracea germplasm resources resistant to Plutella xylostella (L.)

Abstract BACKGROUND Brassica oleracea includes many highly nutritious and widely consumed vegetable crops, yet it is severely threatened by Plutella xylostella , a notorious pest in agriculture. The insect‐resistant traits developed by host plants over hundreds of millions of years provide one of the most promising methods for pest control, which is why we have screened germplasm for resistance to P. xylostella . Among 50 B. oleracea germplasm resources, we identified a key variety, DM187, that caused 53% mortality in larvae and inhibited the development and reproduction of this moth species. RESULTS In this study, we collected and cultivated 50 B. oleracea germplasm resources and evaluated their resistance to P. xylostella . Among these germplasm resources, larvae feeding on DM187 caused the least leaf damage and exhibited the highest mortality rate. Moreover, DM187 significantly inhibited the larval length, larval weight, pupation rate, pupal weight, and adult egg production of surviving P. xylostella . Furthermore, ovarian anatomy showed that DM187 resulted in incomplete ovarian development and a reduced egg count in adult females. CONCLUSION Our findings indicate that the B. oleracea germplasm DM187 significantly impairs the survival, development, and reproductive capacity of P. xylostella . These findings provide a theoretical basis for the identification and utilization of natural insect‐resistant resources in vegetables, as well as for research on insect‐resistant breeding, and offer a strategy for the effective management of pests in agricultural settings. © 2026 Society of Chemical Industry.