Insecticide effect of wild plant powders on bean weevil (Zabrotes subfasciatus Boheman; Coleoptera: Bruchidae) in vitro

powders by four doses: 0.0, 0.1, 0.5 and 1.0%) was used. Results from residual effect and germination tests were analyzed with repeated-measures analyses. The highest percent of mortality was obtained with 0.1, 0.5 and 1.0% of Chrysactinia mexicana, and 0.5 and 1.0% of Gliricidia sepium powders . The lowest adult emergence was obtained with leaf powder of C. mexicana, G. sepium, Guazuma ulmifolia, Dyssodia pentachaeta, Dyssodia acerosa, Heterotheca inuloides and Zinnia acerosa, as well as with fruit powder of Crescentia alata and Melia azedarach. Setting 20% as the threshold for maximum grain damage, the C. mexicana leaf powder reduced damage when administered at 0.5 and 1.0%. C. mexicana, D. acerosa, D. pentachaeta, G. ulmifolia (fruit), H. inuloides, L. tridentata, D. stramonium and Z. acerosa powders had a significant repellent effect on Z. subfasciatus . The toxic effect of C. mexicana and G. sepium lasted 4 weeks. Grain germination was only reduced by G. sepium . Finally, 1.0% of C. mexicana led to the highest mortality of Z. subfasciatus eggs and the lowest percentage of damaged grain.