[Effects of biocontrol strain BZJN1 and streptoprofen on physicochemical properties and bacteria structure of rhizosphere soil of Atractylodes macrocephala].

Soil microorganisms are one of the important biological indictors of soil quality and can reflct the comprehensive ecological environment characteristics of the soil. The research of soil microbial diversity is the key to know the ecological functions and balance with soil. In this paper, high-throughput sequencing on PCR-amplified 16 S rRNA gene V3-V4 fragments was used to determine the bacterial diversity in rhizosphere soil of A. macrocephala under the treatment with BZJN1 or streptoprofen. The results showed that there were no significant differences of the bacteria in A. macrocephala rhizosphere soil of the streptoprofen treatment group and the biocontrol BZJN1 treatment group. All the soil bacteria was classified into 25 categories,67 classes, 108 orders, 167 families and 271 generas, except some unidentified bacteria. Proteobacteria(30.7%-34.8%) was the dominant phylum, of which Alphaproteobacteria(16.8%-18.5%) was the dominant subgroup. Compared with the control group, the relative abundance of multiple phylums bacteria in the rhizosphere soil of A. macrocephala was significantly changed in the streptoprofen treatment group and the biocontrol BZJN1 treatment group. In addition, RDA analysis showed that there was connection with different environmental factors and microbial communities. The abundance of the three genera in the rhizosphere soil of A. macrocephala was significantly positively correlated with Invertase, Urease and AP. PICRUSt function prediction results showed that BZNJ1 could enhance some bacterial functions and promote the plant growth. Biocontrol is a new type of green and safety control pest method. BZNJ1 significantly enhances some bacterial functions on the basis of effectively preventing root rot of A. macrocephala and promoting plant growth, and has no significant effect on the soil bacterial community structure. All the results can provide theoretical support for popularization of BZNJ1.