有机硅对甲氨基阿维菌素苯甲酸盐防治甜菜夜蛾的增效活性研究

Synergistic Activity of Organosilicone to Emamectin Benzoate against Spodoptera exigua

为研究有机硅助剂对甲氨基阿维菌素苯甲酸盐的增效活性,在测定有机硅水溶液的表面张力及其在固体表面的扩展性能的基础上,采用喷雾法测定了添加有机硅的5%甲氨基阿维菌素苯甲酸盐WDG对甜菜夜蛾的生物活性的影响。结果表明,有机硅可显著降低水溶液的表面张力,在0.01%的浓度下其表面张力可降至26mN/m;有机硅可提高液滴在固体表面上的扩展,10μL0.01%的水溶液扩展直径达34mm。室内毒力测定结果表明,当有机硅添加量为1%~5%时,5%甲氨基阿维菌素苯甲酸盐WDG对甜菜夜蛾有显著的增效作用,当添加量高于5%时增效增幅缓慢。大田试验结果表明,添加5%有机硅的5%甲氨基阿维菌素苯甲酸盐WDG33mg/L药后3天和7天对甜菜夜蛾防效分别为81.57%和82.66%,显著优于对照药剂5%甲氨基阿维菌素苯甲酸盐WDG33mg/L、24%氰氟虫腙SC96mg/L、5%氯虫苯甲酰胺SC33mg/L、20%氟虫双酰胺WDG40mg/L和15%精茚虫威EC43mg/L处理。

Based on the determination for the surface tension of organosilicone solution and its expansion on the solid surface, the bioactivity of 5% WDG emamectin benzoate with organosilicone against Spodoptera exigua using spraying method was determined to study synergistic activity of organosilicone to emamectin benzoate. The determination results showed that the organosilicone significantly reduced the surface tension of aqueous solution. The surface tension of 0.01% organosilicone was reduced down to 26 mN/m. The organosilicone significantly raised the expansion of liquid drop on the solid surface. The expanding diameter of 0.01% organosilicone at 10 μL was 34 mm. The laboratory bioassay results indicated that there were significant synergistic activity of organosilicone to emamectin benzoate against S. exigua while the additional amount of organosilicone were 1%-5%, and a slow increasing rate of synergistic activity while the additional amount of organosilicone was higher than 5%. The results in a field trial showed that the efficacy of 5% WDG emamectin benzoate with 5% organosilicone at 33 mg/L against S. exigua were 81.57 and 82.66% on the third day and on the seventh day after spraying insecticide, respectively, and significantly higher than those of 5% WDG emamectin benzoate at 33 mg/L, 24% SC metaflumizone at 96 mg/L, 5% SC chlorantraniliprole at 33 mg/L, 20% WDG flubendiamide at 40 mg/L and 15% EC indoxacarb at 43 mg/L.