【摘要】 从作物茎内和棉田土中分离纯化到１９３株细菌和９０株真菌，通过平板对峙法筛选出对棉铃疫菌具拮抗作用的细菌２６株和真菌１６株。室内离体棉铃生测表明，施用拮抗菌（芽孢杆菌ＭＢ－３、ＭＢ－７、ＭＢ－８、ＢＣ－１）２４小时后再接种棉铃疫菌比施用拮抗菌后马上接种棉铃疫菌的防治效果要好，可达６０％～８０％。田间试验结果显示，８月初仅喷施一次，ＭＢ－３和ＭＢ－７的相对防效达３４．９％和４５．４％，明显优于对照化学药剂。此外，对拮抗菌的拮抗作用机理也进行了初步讨论。更多还原

【Abstract】 193 strains of bacteria and 90 strains of fungi were isolated and purified from crop stalks and cotton soil samples. Among them 26 strains of antagonistic bacteria and antagonistic fungi to Phytophthora boehmeriae were selected by using pair culture method. The bioassay indicated that the treatment of inoculating sporangia of P.boehmeriae on cotton bolls 24 h after applying the antagonistic bacteria (Bacillus sp. MB 3, MB 7, MB 8, BC 1) was much better than the treatment of inoculating the sporangia immediately after applying the bacteria. The control effects were 60%-80% and 30%-40% respectively. The relative control effects against cotton boll phytophthora blight by MB 3 and MB 7 were 34.9% and 45.4% in the field testing, and were significantly higher than that in the chemical control. In addition, the action mechanism of antagonists were also briefly discussed.更多还原