甜菜夜蛾田间种群的药剂敏感性测定

Determination of susceptibility in field populations of Spodoptera exigua to insecticides

采用浸叶法测定福建省4个甜菜夜蛾田间种群对9种杀虫剂的敏感性。结果表明,甜菜夜蛾田间种群对乙酰甲胺磷、氯氰菊酯、毒死蜱、灭多威、顺式氯氰菊酯、定虫隆、氟虫脲、虫螨腈、虫酰肼的敏感性差异明显,LC50值分别为5272.75-6799.33、2387.34-3741.94、198.86-621.55、324.55-1124.94、133.20-399.67、19.34-72.68、38.92-134.11、2.38-3.06和4.84-5.76 mg.L-1;甜菜夜蛾田间种群对杀虫剂的敏感性在不同地区间也存在明显差异。2001-2002年,福州和漳州甜菜夜蛾种群对虫螨腈的敏感性分别下降3.96和5.30倍,福州种群对虫酰肼、顺式氯氰菊酯、毒死蜱和灭多威的敏感性也分别下降3.60、3.61、2.87和1.43倍,但田间种群对定虫隆、氟虫脲的敏感性有所恢复。

Susceptibility to 9 insecticides in 4 field populations of beet armyworm （ Spodoptera exigua ） was determined through exposure of sccond-instar larvae to dipped vegetable leaves. The values of LC50 of acephate, cypermethrin, chlorpyrifos, methomyl, alphacypermethrin, chlorfluazuron, flufenoxuron, chlorfenapyr, and spinosad to S. exigua were 5272.75 - 6799.33 mg· L^-1, 2387.34 - 3741.94 mg· L^-1, 198.86 - 621.55 mg· L^-1, 324.55 - 1124.94 mg·L^-1, 133.20 -399.67 mg·L^-1, 19.34 -72.68 mg·L^-1, 38.92- 134.11 mg·L^-1, 2.38 -3.06 mg·L^-1 and 4.84 -5.76 mg· L^-1 respectively. The results indicated that the insecticide susceptibility could be significantly varied due to the difference of vegetable growth areas. From 2001 to 2002, susceptibility in field populations of S. exigua decreased to Chlorfenapyr, spinosad, alphaeypermethrin, chlorpyrifos, methomyl and increased to chlorfluazuron and flufenoxuron.