Repellency and Toxicity of Eight Plant Extracts against the Western Flower Thrips, Frankliniella occidentalis

We investigated the repellency and toxicity of eight plant extracts containing celangulin, cnidium lactone, matrine, nicotine, pyrethrins, rotenone, stemonine veratrine against western flower thrips (Frankliniella occidentalis Pergande; Thysanoptera: Thripidae). Flowers treated with 0.05% rotenone harbored fewer in two- multiple-choice bioassays. When evaluated at concentrations varying from 0.005% to 0.1% two-choice bioassays, pyrethrins were most repellent 0.01% 0.1%, nicotine was 0.025%. Mortality 76% 48 h, 78% 0.5% 72 100% h after contact fresh (<1-d-old) residue. Effective residue age 1 d for 5 aged residual Celangulin, matrine did not provide sufficient toxicity. Stemonine had inconsistent results. Therefore, additional evaluation its potential as a botanical insecticide will be needed. sprayed onto whole plants, caused unacceptable damage flowers, suggesting that final formulation need modified improve crop safety.