# Evaluating antibiosis resistance to cabbage aphid (Brevicoryne brassicae L., 1758) in vegetable brassicas (Brassica oleracea L.) and related C‐genome brassica species

## TL;DR

Researchers tested 19 Brassica plants to find which ones resist cabbage aphids, identifying two species that significantly limit aphid population growth.

## Contribution

The study identifies Brassica accessions with partial antibiosis resistance to cabbage aphids through controlled bioassays and genetic insights.

## Key findings

- Two Brassica accessions (B. cretica and B. villosa) supported significantly fewer aphids than a commercial control.
- Varietal effects on aphid pre-reproductive period explained 53.9% of resistance variation.
- Eight accessions showed significant differences in aphid reproduction and population growth metrics.

## Abstract

Nineteen Brassica accessions from four C‐genome species were screened under controlled environment conditions for their effects on the development of the cabbage aphid, Brevicoryne brassicae. The aim was to identify accessions with antibiosis host plant resistance (HPR) to B. brassicae. Candidate Brassica accessions were selected because of (i) upregulation of transcription factors gene orthologues acting within the jasmonic acid signalling pathway, or (ii) having been reported in the 1990s as partially resistant to cabbage aphid. Accessions were evaluated by placing three 1‐day‐old aphid nymphs on six true leaf stage plants and recording the aphid population size 14 days later.

There was significant (GLM, P < 0.05) variation in aphid population size between the accessions. Aphid populations on the most resistant accessions were approximately one third the size of those on the most susceptible accessions. Two accessions (B. cretica, B. villosa) supported significantly fewer aphids compared to a commercial variety of B. oleracea used as a reference control. Eight accessions (including B. cretica, B. oleracea and B. villosa) were selected for further study of varietal effects upon aphid biology. Significant differences in B. brassicae reproduction, intrinsic rate of increase, and population doubling time were identified between these eight accessions.

Linear regression analysis identified that HPR was explained mainly by varietal effects on aphid pre‐reproductive period, which accounted for 53.9% of the variation in population development resistance screening results. Partial HPR could be a valuable trait for plant breeding to limit aphid population development as part of an integrated pest management strategy. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Nineteen Brassica accessions were screened for antibiosis resistance to Brevicoryne brassicae. Significant variation in resistance was identified. Detailed bioassays suggest that varietal effects upon aphid pre‐reproductive period conferred observed resistance.