Rhizosphere Bacterial Community Characteristics and Function of Five Limestone Endemic Plants

Abstract:

To understand the similarities and differences in the rhizosphere bacterial communities of different limestone endemic plants, five species of limestone endemic plants in northern Guangdong were studied, including Saxifraga daqiaoensis, Begonia leprosa, Primulina alutacea, P. polycephala and P. yangshanensis. The rhizosphere bacterial community characteristics and functional component of five limestone endemic plants were analysed by using high-throughput 16S rDNA sequencing and bioinformatics methods. The results showed that 42 phyla, 113 classes, 250 orders, 315 families, and 498 genera bacteria were detected in rhizosphere soil of five plants. Chloroflexi, Bacteroidetes, Actinobacteria, Planctomycetes, Proteobacteria and Acidobacteria were the dominant phyla. Heatmap analysis indicated that the soil physical and chemical factors, including available phosphorus, exchangeable calcium, ammonium nitrogen, soil organic matter, pondus hydrogenii and total nitrogen, played important roles in the composition of bacterial community. The LEfSe analysis showed that different plants enriched different rhizosphere bacterial population. The composition and function of the rhizosphere bacterial community of B. leprosa was significantly different from those of the other four plants. The prediction of PICRUSt2 function showed that the rhizosphere bacterial communities of five plants were the most active in metabolism. The function prediction of FARPOTAX showed that chemoheterotrophy, aerobic chemoheterotrophy, nitrification and aerobic ammonia oxidation were the common dominant functional population in the rhizosphere bacteria of five plants. These functional bacteria play an important role in helping plants grow and develop. It would provide soil microenvironment data for the introduction and domestication of endemic plants in limestone.

Key words:Limestone;Endemic plant;Rhizosphere;Bacteria;Community structure;Function prediction