Harnessing key bacteria from suppressive soil to mitigate banana Panama disease

Abstract

Soil microbiomes play a pivotal role in shaping plant health and their ability to suppress the pathogens. However, the specific microbial features that confer disease suppression in agricultural soils have remained unknown. In this study, we aim to elucidate the mechanistic roles of soil key bacteria contributing to disease suppression in banana Panama disease by using a comprehensive soil survey focusing on suppressive, and conducive soils. Through an initial field survey across twelve paired locations, we identified five fields with significantly lower pathogen abundances compared to their co-located counterparts. Subsequent greenhouse experiments validated the disease-suppressive nature of soils collected from Jianfeng (JF) and Lingao (LG), both exhibiting low pathogen densities. Furthermore, four OTUs classified as Massilia (OTU44), Flavisolibacter (OTU396), Brevundimonas (OTU632) and Pseudomonas (OTU731), respectively, were identified as key players in suppressing pathogen invasion as they were significantly enriched in suppresive groups and pathogen inoculated treatments. The present results might suggest a vital link between these soil bacteria and pathogen inhibition in banana rhizosphere via a greenhouse experiment. The abundance of nonribosomal peptide synthetase (NRPS) genes, which was responsible for antibiotic synthesis and significantly enriched in the banana rhizosphere after beneficial microorganism inoculation, displayed a significant and negative correlation with pathogen abundance while a positive correlation with relative abundance of Pseudomonas. This result suggests that the up-regulation of NRPS genes may play a key role in bolstering banana plant immunity. These findings not only provide promising biocontrol strategies but also offer valuable insights into the dynamic relationship between soil microbiomes and plant physiology, paving the way for sustainable agriculture and disease management.