[Effects of bacterial consortium EG03 on control of pepper bacterial wilt and rhizosphere microbial community characteristics in fields].

Bacterial consortium EG03, consisted of several different antagonistic bacteria against Ralstonia solanacearum, was demonstrated to efficiently control bacterial wilt of pepper in field with a biocontrol efficacy of 85.8%. The traditional dilution plate method, the most probable number (MPN) method and Biolog system were adopted to determine effects of EG03 on characteristics of microbial community in pepper rhizosphere. It's shown that EGO3's effects on microbial community in pepper rhizospheric soil varied with time. There were an increase in the number of fungus and Bacillus spp. to some extent and a significant increase in that of nitrogen-fixing bacteria. Biolog analysis showed that the curve between average well color development (AWCD) and incubation time was S-shaped for all the treatments and that the AWCD of pepper rhizospheric soil at the early stage was higher than at the late stage. The analysis of carbon source utilization showed that EG03 decreased microbial utilization of carbon source in short-term, and the microbial community of pepper rhizospheric soil at the late stage composed mainly of microbes depended on sugars as carbon resource. EG03 treatment could decrease the five microbial diversity indices of rhizospheric microbes in short term, then increased those indices instead, especially with significant (P < 0.05) increases in Simpson index and McIntosh evenness.