Multi-omics reveals the sugarcane rhizosphere soil metabolism-microbiota interactions affected by drought stress

Abstract

Drought is considered one of the most damaging stresses affecting crop productivity. Although rhizosphere bacterial communities contribute to improved crop resistance, little is known about the dynamics of these communities in sugarcane under various drought conditions. The rhizosphere bacterial community structure results from a series of complex interactions and feedback between plant roots, bacteria, and the soil physicochemical environment. Therefore, in the current study, we assessed the impact of root phenomes, soil metabolites, soil nutrients, and other multi-omics factors on rhizosphere bacterial community structure under different levels of drought stress. The results showed that different degrees of drought stress may strongly affect bacterial community structure and function by affecting rhizosphere soil metabolite composition. Specifically, sugarcane under mild drought may improve soil nutrient availability and provide an abundant carbon source for bacteria through diversifying rhizosphere soil metabolites (maybe via root exudation). In addition, rhizosphere bacteria may also produce derived metabolites to cross-feed other rhizosphere bacteria to stabilize the bacterial community under mild drought. When drought stress intensifies, the hosts recruit specific bacterial populations to resist drought stress by releasing metabolites and reducing community diversity through this recruitment. In particular, we found that Streptomyces had the greatest contribution to the stress-related microbiota recruited by sugarcane under high drought stress levels. This may be an important target for sugarcane drought-resistance microbiome engineering. This study provides a novel theoretical foundation for improving the stress resistance of sugarcane under different drought stress levels by optimizing the bacterial community.