【摘要】 黄杜鹃 (Rhododendronmolle)中活性最高的化合物闹羊花素 (Rhodojaponin) -Ⅲ在花、嫩叶、根、茎中的含量分别为 0 2 0 %、0 1 4 %、0 1 1 %、0 0 8% ,其花、嫩叶、根的粗提物对菜粉蝶 5龄幼虫和斜纹夜蛾 3龄幼虫具有一定的拒食作用 ,而茎无明显的拒食效果 黄杜鹃花、嫩叶、根、茎各部位甲醇粗提物在 φ =1 0 0 %时对菜粉蝶 5龄幼虫 2 4h的拒食率分别为 92 76 %、86 78%、74 90 %、6 3 80 % ,对斜纹夜蛾 3龄幼虫的拒食率分别为 89 94%、80 0 6 %、73 4 8%和 6 3 2 2 % ,Rhodojaponin -Ⅲ的含量与其拒食活性成正相关更多还原

【Abstract】 Rhodojaponin-Ⅲ was the main toxic component of Rhododendron molle and the content of the flower ,leaf ,foot and stem was about 0.20%,0.14%,0.11% and 0.08%,respectively. Treatment with 1% ethanol extracts of the flower, leaf and foot against the larvae of Pieris rapae and Spodoptera litura showed high antifeeding, the antifeedant rate of flower, leaf and foot to 5th instar larvae of P. rapae was 92.76%, 86.78%, 74.90% and to 3th instar larvae of S. litura was 89.94%, 80.06%, 73.48%, respectively, but the extract of the stems had no obvious antifeedant.The content of Rhodojaponin-Ⅲ had good positive relationship to its antifeedant ratio.更多还原