Control effect of combining biocontrol strains against Fusarium _oxysporium f. sp. niveum and Verticillium dahliae | 不同生防放线菌组合防治枯、黄萎病研究

Chinese. 探讨优良放线菌及其组合对西瓜枯萎病和茄子黄萎病的生物防效，筛选出具有良好防效和促生作用的复合菌株。采用离体抑菌作用测定法和温室人工接菌法，研究不同生防放线菌及其组合对西瓜枯萎病和茄子黄萎病的防效和促生效果。离体抑菌作用测定结果表明，菌株SC11和SE2的菌体、发酵液和发酵滤液对大丽轮枝菌和西瓜枯萎菌均表现出显著的抑制作用，孢子萌发抑制率高；盆栽试验表明，菌株SC11和SC1复配的C2组合对西瓜枯萎病和茄子黄萎病防效显著，防效分别达到84.93%和71.48%，且高于各菌株单一使用的效果；C3组合的发酵液对西瓜的株高、叶面积和叶绿素含量等生理指标影响突出，经C3处理后的西瓜根系还原强度值最大，对茄子的促生作用仅次于菌株SF6。生防放线菌组合的防病促生作用优于单个菌株，组合菌株间通过协同作用可达到优势互补，只有全面考虑各菌株的习性并进行合适的组合，才能充分发挥其生防效果。

English. Five actinomycetes strains having certain inhibiting capability were screened as material to study the control effect of the actinomycetes and five combinations on watermelon Fusarium wilt and Eggplant Verticillium wilt, and to filter the combining biocontrol strains which have better biocontrol efficacy and growth promotion. The biocontrol efficacy and growth promotion of single and combining strains were analyzed by antagonistic activity in vitro and manual inoculation in vivo. Strain SC11 and SE2 had significant inhibiting effect on Fusarium oxysporium f. sp. niveum and Verticillium dahliae in vitro. Inhibiting rate on conidia germination was also high; in greenhouse experimemt, 84.93% control ratio to Fusarium oxysporium f. sp. niveum and 71.48% to Verticillium dahliae were found by C2; The fermentation broth of C3 had the most significant effect for every index of watermelon. The effect on reduction intensity of watermelon rootage was obvious. For eggplant, the growth promotion was only inferior to strain SF6. These results suggested that the control effect and growth promotion of combining biocontrol strains are significantly higher than individual, and combining strains express complementary biocontrol activities by collaboration. There is no correlation between the number of strains and control effect, only proper combinations of biocontrol strains can enhance disease control effect.