高含量苏云金杆菌可湿性粉剂防治茶尺蠖田间药效试验

Field Efficacy of Bacillus thuringiensis with High Level of Insecticidal Crystal Protein against Ectropis obliqua

在鄂东南茶叶种植区,采用喷雾法实施了自制高含量苏云金杆菌（Bacillus thuringiensis）（50000 IU/mg苏云金杆菌可湿性粉剂）防治茶尺蠖（Ectropis obliqua Prout）的田间药效试验。结果表明,50000 IU/mg苏云金杆菌可湿性粉剂对茶尺蠖1-2龄幼虫的田间防治效果随着施药剂量的增加与药后时间的延长而升高,每公顷使用量900-450 g,药后1 d对茶尺蠖1-2龄幼虫防效为36.94%-28.14%；药后3 d防效达到86.35%-77.96%；药后7 d对茶尺蠖幼虫防效显著,达到94.44%-86.43%,每公顷施药900-675 g与对照药剂2.5%联苯菊酯EC无显著差异。

In the southeast of Hubei tea regions,using a spray method,the field efficacy of Bacillus thuringiensis （BT） with high level of insecticidal crystal protein （50 000 IU/mg BT WP, with crystal protein content＆gt;7.0%） against Ectropis obliqua Prout was tested. The results showed that the amount 50 000 IU/mg of BT WP against 1-2 instar larvae of E. obliqua was 900-450 g per hectare,with significant control efficacy, the control effect reached 94.44% and 86.43% respectively after using pesticide 7 days later,the control effect reached 36.94% and 28.14% respectively after using pesticide 1 days later, the control effect reached 86.35% and 77.96% respectively after using pesticide 3 days later. In this field test,the control effect of BT （900-675 g per hectare） was the same as synthetic pesticide named 2.5% bifenthrin EC with no significant difference after using pesticide 7 days later.