甲氧虫酰肼和氯虫苯甲酰胺混配对甜菜夜蛾的增效作用及田间防效

采用浸叶法和田间小区试验分别测定了甲氧虫酰肼和氯虫苯甲酰胺的混配剂对甜菜夜蛾的增效作用和田间防治效果。结果表明:甲氧虫酰肼和氯虫苯甲酰胺混配对甜菜夜蛾具有最大增效作用的质量比为3.0︰2.0,其共毒系数为167.1;药后1 d,按上述比例配制成的10%甲氧虫酰肼·氯虫苯酰胺悬浮剂37.5 g.a.i./hm~2和45.0 g.a.i./hm2两个处理对汝城县和兴国县2个地理种群的甜菜夜蛾防治效果均在85.15%以上,药后10 d的防效均在86.33%以上,表明该混配剂对甜菜夜蛾具有良好的速效性和持效性,值得推广应用。建议10%甲氧虫酰肼·氯虫苯酰胺悬浮剂的施用量为37.5~45.0 g.a.i./hm~2,在甜菜夜蛾低龄幼虫高峰期施用。

Synergism and Field Control Effect of Mixtures of Methoxyfenozide and Chlorantraniliprole Against Spodoptera exigua

The indoor leaf-dipping bioassay and field plot tests were conducted respectively to research the synergism and field control effects of mixtures of methoxyfenozide and chlorantraniliprole against,Spodoptera exigua. The best synergistic effect was discovered in the mass ratio of 3.0:2.0 (methoxyfenozide:chlorantraniliprole), and the co-toxicity coefficient of this mixture against Spodoptera exigua was 167.1. On the first after spraying 37.5 g.a.i./hm2 or 45 g.a.i./hm210% methoxyfenozide·chlorantraniliprole (3.0:2.0) SC in field, its control effect againstSpodoptera exigua populations in 2 different districts was over 85.15%, and over 86.33% on the 10th day. The above results indicated that 10% methoxyfenozide·chlorantraniliprole (3.0:2.0) SC showed better rapidly and durable control effect against Spodoptera exigua. It was suggested that 10% methoxyfenozide·chlorantraniliprole (3.0:2.0) SC should be sprayed at the dosage of 37.5-45 g.a.i./hm2 at the low-instar larva peak stage ofSpodoptera exigua.