Analysis on Metabolic Functional Diversity of Rhizosphere Microbial Communities of Pennisetum giganteum

Objective The study aimed to explore the utilization of different carbon sources by microbial communities in rhizophere and non-rhizosphere soil, and identify the influences of rhizophere soil microbial functional diversities so as to provide a theoretical basis for ecological remediation with Pennisetum giganteum.

Method The samples of rhizophere and non-rhizosphere soils of P. giganteum were collected in Pintan Base, Fujian Province. Biolog- ECO method was used to study the characteristics of carbon source utilization by microorganisms in the rhizophere and nonrhizosphere soils of P. giganteum in order to reveal the differences in carbon source utilization and main factors influencing such differences.

Result Compared with control, the metabolic activity of microorganisms in the rhizophere soil of P. giganteum was higher than that in the non-rhizophere soil. The results of diversity analysis showed that, compared with the non-rhizophere soil samples, the Simpson diversity index, Shannon diversity index and Brillouin diversity index of the rhizophere soil samples were little higher, and no obvious difference was found. Principal component analysis (PCA) showed that there were 22 and 6 kinds of carbon sources that contributed greatly to PCA 1 and PCA 2, respectively, and carbohydrates were the main carbon sources for rhizosphere soil of P. giganteum.

Conclusion The microbial community of P. giganteum rhizosphere soil has higher carbon source utilization and metabolic diversity than that of non-rhizosphere soil