Microbacterium aurantiacum GX14001 promotes the growth of tomato plants by altering the microbial community structure in rhizosphere soil

Abstract:

As autotoxic substances secreted by plant roots, phenolic acids such as p-hydroxybenzoic acid (PHBA), are the main factors causing continuous cropping obstacles.Objective To study the effects of Microbacterium aurantiacum on the growth of tomato plants and the microbial community structure in rhizosphere soil under PHBA stress.Methods We irrigated tomato rhizosphere with the suspension of M. aurantiacum GX14001 and then measured the growth traits of tomato plants and the soil microbial community changes in the rhizosphere soil.Results Under the PHBA treatment, GX14001 significantly promoted the growth of tomato plants, increasing the leaf area, stem diameter, and plant height by 244.0%, 156.5%, and 128.0%, respectively. GX14001 increased the richness but did not cause changes in the diversity of bacteria in the rhizosphere soil. Meanwhile, it decreased the richness and diversity of fungi in the rhizosphere soil. At the phylum level, compared with the control group, the GX14001 group showed increased relative abundance of Actinobacteriota, Chloroflexi, and Proteobacteria, with Ascomycetes as the dominant fungal phylum.Conclusion M. aurantiacum GX14001 promotes the growth of tomato plants by changing the microbial community structure in the rhizosphere soil. It increases the relative abundance of beneficial microorganisms in the soil to create a favorable environment for tomato growth.