Synthetic Microbial Community Members Interact to Metabolize Caproic Acid to Inhibit Potato Dry Rot Disease

Abstract

The potato dry rot disease caused by Fusarium spp. seriously reduces potato yield and threatens human health. However, potential biocontrol agents cannot guarantee the stability and activity of biocontrol. Here, 18 synthetic microbial communities of different scales were constructed, and the synthetic microbial communities with the best biocontrol effect on potato dry rot disease were screened through in vitro and in vivo experiments. The results show that the synthetic community composed of Paenibacillus amylolyticus, Pseudomonas putida, Acinetobacter calcoaceticus, Serratia proteamaculans, Actinomycetia bacterium and Bacillus subtilis has the best biocontrol activity. Metabolomics results show that Serratia protoamaculans interacts with other member strains to produce caproic acid and reduce the disease index to 38.01%. Furthermore, the mycelial growth inhibition after treatment with caproic acid was 77.54%, and flow cytometry analysis showed that the living conidia rate after treatment with caproic acid was 11.2%. This study provides potential value for the application of synthetic microbial communities in potatoes, as well as the interaction mechanisms between member strains of synthetic microbial communities.

A systematic discussion and comparison of the construction methods of synthetic microbial community

“…Preliminary assessments for inhibitory activity against synthetic microbial communities were performed ex vitro using potato tissues. Ultimately, the most effective synthetic community was identified, which directly suppressed the occurrence of potato dry rot disease by inhibiting the mycelium and conidia of Fusarium species, thereby enhancing the biocontrol activity against potato dry rot [ 94 ]. Bai et al isolated and cultured bacteria from healthy Arabidopsis thaliana inter-roots and leaves by cell sorting and colony selection in liquid medium, in 96-well microtiter plates.…”

“… Agriculture Synthetic microbial communities can effectively enhance plant growth and their adaptive capacity to abiotic stress [ 24 , 48 , [85] , [86] , [87] , [88] , [89] ]. The interaction between synthetic microbial communities and plants can enhance the host's ability to resist pathogen invasion, which is crucial for plant protection and biological control [ 65 , [90] , [91] , [92] , [93] , [94] , [95] ]. …”

“…The interaction between synthetic microbial communities and plants can enhance the host's ability to resist pathogen invasion, which is crucial for plant protection and biological control [ 65 , [90] , [91] , [92] , [93] , [94] , [95] ].…”