Different effects of soil bacterial communities affected by biocontrol agent YH-07 on tomato wilt inhibition.

Bio-organic fertilizers based on biocontrol microorganisms have been widely applied to suppress soilborne diseases and improve crop yields. Studies on beneficial biocontrol agents have promoted the development of the bio-organic fertilizers in China. Our previous study demonstrated that a biocontrol agent, sp. YH-07, can inhibit the growth of the plant pathogen . In the present study, we investigated the effects of this biocontrol agent on tomato wilt and used the illumina-based sequencing approach to characterize the variations in soil bacterial communities in a potted experiment. The aim of our study was to explore the potential correlation among bacterial communities, wilt suppression, and soil properties after application of the biocontrol agent YH-07. The results showed that application of sp. YH-07 effectively controlled outbreaks of tomato wilt. The illumina MiSeq sequencing showed that was the predominant phylum in the soil samples. Bacterial community composition and structure varied under different soil treatments, , the relative abundance of and was significantly increased in the YH treatment, and were decreased in the YH treatment compared with the CK treatment. Additionally, the correlation results showed that the soil organic matter and available phosphorus and potassium were higher after YH-07 application, and they were positively correlated with bacterial community. The redundancy analysis showed and were the dominant genera after YH and CK treatments, respectively, and correlations with tomato wilt incidence were negative and positive, respectively.