Study On Genetic Diversity Of Botrytis Cinerea And Antagonism Of Three Biocontrol Bacteria Strains Against B. Cinerea In Xinjiang

Botrytis cinerea is an important plants pathogen. Nowdays, the pathogenicity and genetic diversity of this disease are lack of sestemetic research. Thirteen isolates of B. cinerea obtained from different hosts in three ecological regions of Xinjiang, were inoculated artificially in unorganized leaves of seven hosts, and the pathogenicity of these pathogens was confirmed by the lesion size. The results showed that the pathogenicity of thirteen isolates had obvious difference, and the pathogenicity type of these isolates were divided into strong, medium and weak types. In particular, which caused Hetian tomato grey mold and Yili Tekesi tomato grey mold, the isolates 's pathogenicity were the strongest among all isolates; which caused Yili Zhaosu tomato grey mold, pathogenicity of this isolate was the weakest. According to lesion size in the leaves of different hosts, thirteen isolates were divided into 4 groups. Genecity diversity of twenty-six isolates of B. cinerea in different regions and hosts of Xinjiang also were analized by RAPD method. By random amplified polymorphic DNA (RAPD) analysis, almost all of the isolates were genetically different, and twenty-six isolates were divided into 6 groups. Although relationships was not found between pathogenicity and sampling host,sampling place, the clear correlation was found between sampling place and RAPD patterns.The study on the biocontrol efficacy of the Bacillus strains A57,A178 and N1729 against 13 Botrytis cinerea isolates from the different area in Xinjiang, was performed for evaluating the future application significance of the three strains for the biological control of plant diseases,and providing scientific basis for the future research on their development.The antagonism of three biocontrol bacteria were tested on PDA plate against 13 Botrytis cinerea isolates respectively. By the liquid fermenting and the tiny hole filters, the antagonism of free cell filtrates were detected on PDA plate. The results demonstrate that, the antagonistic activity of A178 strain was the strongest among these three biocontrol bacterium, the average inhibition rate of the strain was 45.67%. The average inhibition rate of free cell filtrates of N1729 strain was 44.61%. A57 strain had the better antagonistic ability to the pathogen, but its free cell filtrates was no effect to the pathogen. These evidences showed that strains A178 and N1729 were the excellent biocontrol materials against Botrytis cinerea with good prospects of development and application.