荸荠枯萎病病原菌及其生物学研究

１９９６－１９９７年用诊断剂地监测，证明冀鲁豫６个棉铃虫种群对三氟氯氰菊酯，氯氰菊酯，灭多威，久效磷和辛硫磷已有较高的抗性效率。其中３３％的样本抗性频率顷５０％以上，５１％的样本抗性频率在２０％－５０％之间，只有１６％的样本抗性频率在２０％以上。点滴法测定结果表明，棉铃虫对三氟氯氰菊酯的抗性指数在４７．倍以上，最高达１９５．６倍。

BIOLOGICAL CHARACTERISTICS OF THE PATHOGENIC FUNGI OF WATER CHESTNUT WILT

High frequency of resistance to cyhalothrin, cypermethrin, methomyl, monocrotophos and phoxin in H. arrnigera collected from Hebei, Henan and Shandong Provinces during 1996-1997 have been detected by diagnostic dose method. Of the examined samples 33% holds a resistance frequency higher than 50%, 51% holds 20% -50% , and the frequency of the rest samples (16%) is lower than 20%. Resistance ratio (RR) of H.armigera to cyhalothrin was found as high as 47. 8-195. 6 folds when detected with topical application method, and 12. 6 - 132. 7 folds for methomyl, 9. 2 - 26. 5 folds for monocrotophos. The resistance ratio obtained from leaf-dipping methos or topical application method show a similar tendency. The RR value was positively related with resistance frequency. Synergistic action of PBO to cyhlaothrin was much more higher than that of DEF, this fact display such a possibility that mixed function oxidase plays as the detoxification factor. Resistance ratio to H. arrnigera in Xinjiang detected by topic application method was lower than 10 folds, but lower than 2 folds when leafdipping method is used.