Combatting glufosinate-induced pepper toxicity: jasmonic acid recruiting rhizosphere bacterial strain Rhodococcus gordoniae.

Abstract

Background: Plant-microbe interactions are essential for mitigating abiotic and biotic stressors by shaping the rhizosphere environment. However, how rhizosphere beneficial bacteria and plant metabolites respond to glufosinate (GLU)-induced toxicity remains largely unknown.

Results: Our study investigates the impact of GLU on chili plant growth and rhizosphere microbiome, emphasizing GLU-induced alterations in amino acid profiles, secondary metabolites, and microbial community composition, with notable enrichment of the Rhodococcus genus. To uncover the underlying mechanisms of Rhodococcus genus-root exudate interactions under GLU stress, we successfully isolated an efficient Rhodococcus gordoniae strain TR-5 from soil samples contaminated with GLU. This strain, isolated from GLU-contaminated soil, demonstrates potential for bioremediation and achieved over 95% GLU degradation efficiency at 35 °C, pH 6.38, and 1% inoculation rate. Through growth analysis, chemotaxis analysis, and molecular docking, caffeic acid disrupts the bacterial strain's metabolic pathways and impedes TR-5 development. In contrast, jasmonic acid (JA) acts as a chemoattractant, promoting bacterial growth and metabolic activity to degrade GLU residues, thereby effectively degrading GLU residues in the soil.

Conclusions: This research indicates that GLU significantly influences the metabolic mechanisms of pepper plants. The optimization of microbial remediation strategies may improve soil remediation efficiency and reduce environmental impacts, highlighting opportunities for integrating microbial remediation into sustainable agricultural practices. Our findings provide insights into the role of JA in attracting and promoting the growth and metabolic activities of the Rhodococcus genus, which could be harnessed to improve soil remediation and plant health under GLU stress. Video Abstract.