黄杜鹃花粗提物及闹羊花素-III对斜纹夜蛾幼虫杀虫活性的研究

Study on the Control Effect of the Crude Extract of Rhododendron molle and Rhodojaponin-Ⅲ to the Larvae of Spodoptera litura larvae

研究了闹羊花素-III防治斜纹夜蛾幼虫的盆栽试验和黄杜鹃花甲醇提取物田间小区的防治试验。盆栽试验结果表明,以浓度500"g/ml的闹羊花素-III处理,第1,3,7天,斜纹夜蛾的虫口减退率分别为53.18%,64.14%和79.73%,处理后5天和10天的叶片保护率分别为63.64%和68.18%,效果优于川楝素(250"g/ml)。田间小区试验结果表明,以2%黄杜鹃花甲醇提取物处理后第1,3,7,10天的防治效果分别为62.03%,81.87%,92.92%和97.88%,优于2.5%功夫乳油的1000倍液的防治效果。

The control effect of methanol extract of the flowers of Rhododendron molle and rhodojaponin-Ⅲ against the larvae of Spodoptera litura were studied in this paper. The results of pot trials in greenhouse showed that after spraying of 500μg/ml onto the cabbage seedlings, which inhibiting rates of the insect population were found to be 53.18%, 64.14% and 79.73% in lday, 3 days and 7 days after treatment respectively, while the rates of leaf protection reach 63.64% in 5 days and 68.18% in 10 days after treatment respectively. This effectiveness was better than that of 250μg/ml Toosendanin. The results of the field trial showed that treatment with 2% methanol extract of the flowers of R. molle could control the larvae of S. liture and the effectiveness were 62.03%, 81.87%, 92.92% and 97.88% in 1,3,7 and 10 days after treatment, respectively. The effect was better than that of 1 000 times Kung Fu （lambda-cyhalothrin）.