球孢白僵菌对韭蛆的室内生物测定和田间效果评价

Indoor Bioassay of Beauveria bassiana against Bradysia odoriphaga and Evaluation on Control Effect in Field

研究了市售150亿孢子/g球孢白僵菌颗粒剂对韭蛆的室内和田间防治效果。室内生测结果表明,随着白僵菌孢子浓度的增大,韭蛆的累计校正死亡率逐渐升高,LT50逐渐减小,1×109个/mL浓度处理累计校正死亡率可达81%。田间药效结果显示,666.7m2用300 g球孢白僵菌颗粒剂防治效果显著优于毒死蜱,其药后7 d防治效果为81.15%;药后21 d虫口减退率为74.47%,防虫效果为85.19%,同时对韭菜的保苗效果为79.37%,与清水对照组的保苗效果一致。

The control effects of Beauveria bassiana（granules at the concentration of 15 billion spores per gram） against Bradysia odoriphaga were studied both by indoor bioassay and field trial.The indoor bioassay results showed that the cumulative corrected mortality of Bradysia odoriphaga increased gradually and the LT50decreased with the increase of Beauveria bassiana spore concentration.At the concentration of 1 × 109spores per milliliter,the cumulative corrected mortality was 81%.The field trial results showed that the control effect of Beauveria bassiana with the dosage of 300 g granules per 666.7m2was significantly superior to chlorpyifos.The control effect was 81.15% after applying for 7 days.The population decline rate and the insecticidal effect were 74.47% and 85.19% respectively after applying for 21 days.Meanwhile,the protected seedling rate of Chinese chive was 79.37%,which was similar to that of fresh water group.