几种药剂对吐伦球坚蚧的毒力及田间防效

Control efficacy and bioassay of several insecticides against Rhodococcus turanicus

为确定防治吐伦球坚蚧效果好的药剂及最佳防治时机,对吐伦球坚蚧越冬、越夏若虫进行了室内毒力测定及田间防效试验。室内毒力测定结果表明,5%啶虫脒乳油对越冬、越夏若虫活性最高,LC50分别为31.268mg/L和22.056mg/L。田间喷雾试验,14.6%噻虫嗪+9.4%高效氯氟氰菊酯悬浮剂对越夏若虫防效达99%以上。5%啶虫脒乳油对越冬若虫防效为98.76%。注干试验,25%噻虫嗪水分散粒剂200倍液和20%吡虫啉乳油50倍液注干15d后,对涌散期若虫防效为90.46%和94.16%;对越夏固定期若虫防效为92.51%和82.57%。以5%啶虫脒乳油和20%吡虫啉乳油对越冬若虫进行喷雾,防治效果与防治时机最佳。

The effective pesticides and perfect time for controlling Rhodococcus turanicus were investigated. Bioassay and field control efficacy of the pesticides against overwintering and oversummering nymphs of R. turanicus were studied. Acetamiprid had the highest activity against the overwintering and oversummering nymphs, with a LC50 of 31. 268 mg/L and 22. 056 mg/L in the laboratory, respectively. In the spring experiment, 14.6% thiamethoxam ＋ 9.4% lambda-cyhalothrin could control more than 99% oversummering nymphs, and 5% acetamiprid could control 98.76% of overwintering nymphs. By trunk injecting, 25% thiamethoxam 200 X and 20% imidacloprid 50X had a control efficacy of 90.46% and 94.16% against the nymphs during incubation period, respectively, and 92.51% and 82.57% against oversummering nymphs during fixed and feeding period after 15 days. 5% acetamiprid and 20% imidacloprid spray had best efficacy against overwintering nymphs. Trunk injection control had best control efficacy against the nymphs during incubation period.