HEALTHY_SOIL_JXHS Metagenomic assembly

To explore the factors influencing the occurrence of bacterial wilt, the differences in the physicochemical properties, microbial community composition and function between rhizosphere soil of tobacco wilt plants infected with bacterial wilt and that of healthy plants in the tobacco planting area of Fuzhou City, Jiangxi Province were analyzed and compared.The results showed that the rhizosphere soil of diseased tobacco exhibited significantly reduced levels of exchangeable potassium, water-soluble potassium, nitrate nitrogen, total nitrogen and pH, in comparison to the rhizosphere soil of healthy plants. Conversely, the available phosphorus content of the rhizosphere soil of diseased tobacco was significantly increased. The amount of Ralstonia solanacearum in soil was negatively correlated with pH, nitrate nitrogen and total nitrogen, and positively correlated with exchangeable potassium and water-soluble potassium. A total of 43 genera were significantly different between the two groups of rhizosphere soil, of which 24 genera were enriched in the rhizosphere of healthy plants, including Ideonella, Rhizophagus, Rhizobacter, Altererythrobacter, and Ignavibacterium associated with plant disease resistance, Thermodesulfovibrio, Syntrophorhabdus, Syntrophus, Chlorobium, Hydrogenophaga, and Limnohabitans associated with soil sulfur metabolism, as well as Ignavibacterium, Ideonella, Derxia, and Azohydromonas associated with soil nitrogen cycling. KEGG functional analysis of the unigenes obtained by metagenomic sequencing also showed that the differential unigenes were significantly enriched in the sulfur metabolism pathway. In addition, the rhizosphere soil of diseased tobacco plants exhibited a higher abundance of antibiotic-producing actinomycetes and an increased load of antibiotic resistance genes compared to that of healthy plants. In general, lower pH value, less content of nitrate nitrogen and total nitrogen, more content of exchangeable potassium and water-soluble potassium could contribute to onset of bacterial wilt, 24 genera including Ideonella, Rhizophagus etc. may construct healthy microecological network in the rhizosphere of tobacco plants, all these factors may interact with each other to control the development of bacterial wilt, complicated interaction network need to be explored further.