Bacillus amyloliquefaciens B1408 suppresses Fusarium wilt in cucumber by regulating the rhizosphere microbial community

Soil-borne diseases are often less severe in organic farms, possibly because of the recruitment of beneficial microorganisms by crops. Here, the suppressiveness of soils from organic, integrated, and conventional farming systems to pepper blight (Phytophthora capsici) were studied in growth chamber experiments. Disease incidence was 41.3% and 34.1% lower in the treatment with soil from the organic farming system than either from the integrated or conventional farming system, respectively. Beta-diversity of rhizospheric microbial communities differed among treatments, with enrichment of Bacillus, Sporosarcina, Acidobacteria Gp5, Gp6, Gp22, and Ignavibacterium by the organic soil. Cultivation-dependent analysis indicated that 50.3% of in vitro antagonists of P. capsici isolated from the rhizosphere of healthy peppers were affiliated to Bacillus. An integration of in vitro antagonists and metagenomic analysis indicated that Bacillus antagonists were higher in the rhizosphere of pepper treated by the organic soil. A microbial consortium of 18 in vitro Bacillus antagonists significantly increased the suppressiveness of soil from the integrated farming system against pepper blight. Overall, soil microbiome under the long-term organic farming system was more suppressive to pepper blight, possibly due to Bacillus antagonism in the rhizosphere. This study provided insights into microbiome management for disease suppressions under greenhouse conditions.

Long-Term Organic Farming Manipulated Rhizospheric Microbiome and Bacillus Antagonism Against Pepper Blight (Phytophthora capsici).

Development of a novel bio-organic fertilizer for the removal of atrazine in soil

Reducing dependence on chemical pesticides is considered as an essential challenge for sustainable crop production. The use of microbial biocontrol agents (MBCAs) is a key component of sustainable pest management. Numerous antagonistic microorganisms are known to suppress plant diseases, but their practical application and commercialization are still limited in part due to poor reliability of their efficacy in the field. Although promising MBCAs achieve remarkable disease control in the laboratory or greenhouse, field control is often unsatisfactory. Thus, for MBCAs to be integrated into crop production, their field performance must be improved to provide the cost-effectiveness and efficacy required by growers. In this review, we highlight recent approaches to enhance the field performance of MBCAs.

Xing Luo

Papers

Development of a novel bio-organic fertilizer for plant growth promotion and suppression of rhizome rot in ginger.