Bacterial community richness shifts the balance between volatile organic compound-mediated microbe-pathogen and microbe-plant interactions

Even though bacteria are important in determining plant growth and health via volatile organic compounds (VOCs), it is unclear how these beneficial effects emerge in multi-species microbiomes. Here we studied this using a model plant-bacteria system, where we manipulated bacterial community richness and composition and determined the subsequent effects on VOC production and VOC-mediated pathogen suppression and plant growth-promotion. We assembled VOC-producing bacterial communities in different richness levels ranging from one to twelve strains using three soil-dwelling bacterial genera (Bacillus, Paenibacillus and Pseudomonas) and investigated how the composition and richness of bacterial community affect the production and functioning of VOCs. We found that VOC production correlated positively with pathogen suppression and plant growth-promotion and that all bacteria produced a diverse set of VOCs. However, while pathogen suppression was maximized at intermediate community richness l...尽管细菌可通过挥发性有机化合物（Volatile Organic Compounds，VOCs）调控植物生长与健康，但目前尚不清楚这些有益效应在多物种微生物组中是如何产生的。本研究以模式植物-细菌系统为研究对象，通过调控细菌群落的丰富度与组成，探究其对VOCs产生、VOCs介导的病原菌抑制以及植物促生效应的后续影响。本研究选取3类土壤栖息细菌属：芽孢杆菌属（Bacillus）、类芽孢杆菌属（Paenibacillus）与假单胞菌属（Pseudomonas），构建了涵盖1至12个菌株的不同丰富度梯度的产VOCs细菌群落，并探究细菌群落的组成与丰富度如何影响VOCs的产生与功能。研究结果显示，VOCs的产生量与病原菌抑制效果、植物促生效应呈显著正相关，且所有供试细菌均可产生多样的VOCs组分。不过，病原菌抑制效果在群落丰富度处于中等水平时达到峰值，但……