Evaluation of Insecticidal Activity of Plant Extracts against the Diamondback Moth, Plutella xylostella (Lepidoptera: Plutellidae) on Vegetable Plant

Urban Farm DB summary

In a South Korean laboratory and field study, ethanol and water extracts of eight plant species were tested for insecticidal activity against diamondback moth (Plutella xylostella) larvae on Korean radish and Korean cabbage using a leaf-disc spray method. Capsicum annuum (chili seed) extract gave the highest activity, 83.3% at 1500 mg/L after 48 hours; in field trials with twelve applications before harvest, Coptis japonica (goldthread) and C. annuum extracts reached control efficacies of 87.4% and 83.7% on Korean radish, and 74.3% and 69.3% (with Chelidonium majus) on Korean cabbage, with no phytotoxic effect on seed germination or seedling growth observed.