印楝素制剂对小菜蛾毒杀和生长发育抑制作用的研究

STUDIES ON THE EFFECTIVENESS AND GROWTH INHIBITORY EFFECT OF MARGOSAN ON DIAMONDBACK MOTH ( Plutella xylostella )

印楝素制剂（ＭａｒｇｏｓａｎＯ）对小菜蛾３龄幼虫具有较好的毒杀和生长发育抑制作用。小菜蛾３龄幼虫连续４ｄ饲喂经１５ｍｇ／Ｌ印楝素制剂处理的叶片时，幼虫和蛹死亡率达８４１２％；化蛹率、羽化率和正常羽化的雌虫生殖力随处理浓度升高而迅速下降；对多种杀虫剂产生抗性的小菜蛾田间品系和敏感品系的毒力无显著差异。

Results of experiments in laboratory showed that margosan O possessed strong insecticidal properties and growth regulatory effects on the 3rd instar larvae of the diamondback moth (DBM). The mortality of the larvae and pupae was 84.21%when the 3rd instar larvae of DBM were fed by the leaves of vegetable sprayed with 15 mg/L margosan O. The pupation, emergence and fecundity of DBM were seriously supppressed by margosan O. Experimental results also proved that the LC 50 was 36.90 mg/L and 28.77 mg/L respectively, on resistant strain and susceptible strain of the 3rd instar larvae of DBM.