Comparison of Bacterial Diversity in the Rhizosphere of Chromolaena odorata (L.) R.M. King and H.Rob. in Different Habitats

Abstract

The invasion of Chromolaena odorata (L.) R.M. King and H.Rob. affects microbial community structure, but seldom do studies focus on bacterial diversity in the rhizosphere of C. odorata from different habitats. To reveal the impacts of C. odorata on bacterial communities in different habitats, diversity and functional groups of bacteria were compared in the rhizosphere soil of C. odorata collected from three habitats: abandoned land, a mature eucalyptus forest (eight-years), and a young eucalyptus forest (one-year). In this study, 3701 OTUs (operational taxonomic units) were obtained by next-generation sequencing. Simpson diversity indexes of bacteria in eucalyptus forests were significantly higher than that in abandoned land. Based on PCoA analysis, significant differences in the composition of bacterial communities were observed among the three habitats. Significant differences in bacterial communities among the three habitats were also demonstrated by biomarkers based on linear discriminant analysis effect size (LEfSe) analysis. Functional prediction analysis showed that the abundance of nitrogen-fixing functional genes in eucalyptus forests was greater than that in abandoned land. Canonical correspondence analysis (CCA) found that the biomass of C. odorata, soil pH, and total phosphorus were the main factors that impacted the microbial community structure. The results highlight the microbial community varied with habitats invaded by C. odorata, providing new evidence for understanding the invasion of C. odorata in different habitats.