防治植物枯、黄萎病的优良放线菌株筛选

采用平板对峙法、生长速率法和组织研磨法对实验室前期获得的放线菌进行测定,以期筛选出对植物枯、黄萎病生防作用较为全面的优良放线菌株。皿内抑菌试验结果表明,菌株SC11的抑菌能力最为突出,对3种靶标菌的平均抑制率接近80%,菌株153、SE2和F46也有较好的抑菌效果,平均抑菌率均超过50%;耐药性试验结果表明,菌株153、SC11耐药性较强,菌株F46在各杀菌剂存在条件下均不能生长;盆栽试验结果表明,菌株153、SC11在不同作物上均有较强的定殖能力,对供试作物种子萌发及植株生长有明显的促进作用。经室外盆栽模拟大田试验证明,153、SC11放线菌具有较好的防病促生效果。总体来看,菌株153和SC11的生防特性较全面,抗菌、耐药、易定殖并且能够促进作物生长,具有一定的应用潜力。

Screening of Advantage Actinomycetes against Fusarium oxysporum and Verticillium dahliae

According to flat confrontation method, growth rate method and organization grinding method, the research further tested the biocontrol characteristics of 10 strains actinomycetes which were obtained after isolating and preliminary screening, with the purpose to screen out the strains which have the most obvious and comprehensive biocontrol characteristics against Fusarium oxysporum f. sp. niveum and Verticillium dahliae .The results of the inhibiting effects experiment indicated that the strain SC11 had the strongest antagonistic effects, with the average inhibition rates of mycelium growth was near to 80%. The strain 153, SE2 and F46 also had obvious antagonistic effects whose average inhibition rates of mycelium growth was more than 50%; the results of drug resistant experiment showed that the strain 153 and SC11 had greater drug resistance, the strain F46 could not grow up when the fungicides exist; in pot culture experiment, the colonization ability of the strain 153 and SC11 were much stronger and they both had different degree of growth promoting effects on the seed germination and the plant growth. At the same time, they had obvious control effect on the Fusarium wilt and Verticilium wilt. The biocontrol characteristics of strain 153 and SC11 are comprehensive. Both of them have the advantages of preventing effects to pathogens, drug resistant, easier for colonization and growth promoting effect on the plants and have a certain potential to be developed and utilized.