青枯病抗性不同的番茄品种根际拮抗菌拮抗能力差异研究

Diversity of Antagonistic Bacteria in Rhizosphere of Tomato Plants with Different Resistance to Ralstonia solonacearum and Corresponding disease-Controlling Efficacy

以植物基因型影响根际微生物的多样性为依据,通过平板拮抗试验,从番茄的感病品种和抗病品种、感病品种的严重发病植株和轻微发病植株根际筛选到36株抬抗菌,不同来源的抬抗菌群落具有不同的特征。严重发病的感病品种植株根际的拮抗菌群落多样性低,仅筛选到1个拮抗菌株,而轻微发病的感病品种和未发病的抗病品种植株根际筛选到的拮抗菌株数较多;抗病品种根际桔抗菌表现出强拮抗能力,而感病品种根际拮抗菌的拮抗能力较弱。测定植株根面和根颈处导管内青枯菌的种群数量、3株拮抗菌的防病效果,发现导管内青枯茵数量与防病效果基本一致,探讨了导管内青枯菌数量作为拮抗菌防病效果指标的可能性。

Based on the principle that plant genotypes influence the diversity of microbial community in rhizosphere, 36 stains antagonistic to Ralstonia solonacearum were screened out on plates from rhizosphere of tomato genotypes resistant (RG) or sensitive (SG) to plant bacterial wilt disease and severely or slightly diseased plants of S. Results showed that only 1 stain was screened out from severely diseased plants of SG, while much more strains were from slightly diseased plants of SG or healthy plants of RG. Strong antagonistic efficacy was observed for those strains from plants of RG, contrasting to the weak antagonistic efficacy for strains from plants of S. It was suggested that the antagonistic bacteria in the rhizosphere of RG plants may be involved in the resistance to Ralstonia solonacearum. The population of Ralstonia solonacearum on the root surface and in the xylem of root neck were investigated, together with the disease-controlling efficacy of 3 selected strains. The amount of Ralstonia solonacearum in xylem was found to be consistent with the disease-controlling efficacy, and thus the possibility of pathogen population in the xylem as an index of disease-controlling efficacy is discussed.