Abstract:

【OBJECTIVE】Understanding the influence of invasion of Mikania micrantha and Bidens pilosa to the bacterial community in the root soils.【METHOD】The PCR-DGGE combined with cloning of V3 region of bacterial 16S rDNA fragments were used to analyze the bacterial community of the rhizospheric soils, which were heavily invaded, newly invaded or non-invaded by the two exotic weeds, Mikania micrantha and Bidens pilosain in Guangzhou.【RESULTS】The analysis of DGGE profiles showed that: comparing with the non-invaded site, the soil examples of the heavily-invaded and the newly-invaded by Mikania micrantha in Guangzhou had the similarity of 59.6% and 54.2%, respectively; the same trend occurred in the soil samples of the heavily-invaded and the newly invaded by Bidens pilosa, the similarity were 60.0% and 58.6%, respectively. The invasion of Mikania micrantha and Bidens pilosa resulted in the changes of uncultivated bacteria which had close relationships to α, β, γ proteus and bacilli in the soils.【CONCLUSION】All those results suggested that the invasion of Mikania micrantha and Bidens pilosa could modified soil microbial community composition, probably create favorable soil environment to benefit themselves.