航空喷雾20%氯虫苯甲酰胺悬浮剂防治美国白蛾试验

Aerial spraying experiment against Hyphantria cunea( Drury) with Chlorantraniliprole 20% SC

为明确20%氯虫苯甲酰胺悬浮剂防治美国白蛾幼虫的最适用药剂量和最佳防治龄期,开展了直升机超低容量喷雾防治试验。结果表明,20%氯虫苯甲酰胺悬浮剂对美国白蛾2~3龄幼虫具有较好的速效性和较长的持效期。在120 m L/hm^2和150 m L/hm^2用药剂量下,美国白蛾2龄幼虫虫口减退率施药后2 d分别为96.5%和100%;3龄幼虫施药后4 d分别为97.5%和99.0%;4龄和5龄幼虫施药后6 d分别为77.8%、83.1%和99.8%、77.9%,施药后7 d均达100%;施药后8 d投放5龄幼虫,7 d后虫口减退率仍在80%左右。在90 m L/hm^2用药剂量下,施药后7 d,仅2龄幼虫虫口减退率达到100%,3龄幼虫虫口减退率为68.6%,4龄和5龄幼虫虫口减退率只有40%左右。航空喷雾20%氯虫苯甲酰胺悬浮剂防治美国白蛾幼虫的最适用药剂量为120~150 m L/hm^2,持效期可达15 d,最佳防治龄期为2~3龄。

In order to charify the most suitable dosage and the best control time of Chlorantraniliprole20% SC against the larvae of Hyphantria cunea（ Drury）,the experiment of helicopter ultralowvolume spraying method was carried out. The results showed that Chlorantraniliprole 20% SC had quicker effect and longer persistent period on 2nd-3rd instar larvae of Hyphantria cunea. Under the dosage of120 m L/hm^2 and 150 m L/hm^2,decrease rate of 2nd instar larvae were 96. 5% and 100% 2 d after application; 3rd instar larvae were 97. 5% and 99. 0% 4 d after application; 4th and 5th instar larvae were77. 8%,83. 1% and 99. 8%,77. 9% 6 d after application and reached 100% 7 d after application; 8 d after the application,decrease rate of 5th instar larvae were about 80% after be put on the tree 7 d later. Under the doseage of 90 m L/hm^2,decrease rate of 2nd instar larvae reached 100% 7 d after application,which were 68. 6% and 40% for 3rd instar larvae and 4th-5th instar larvae respectively. The results showed that the most suitable range was 120-150 m L/hm^2,and the best control period were2nd-3rd instar larvae.