Assessing bacterial communities in the rhizosphere of 8-year-old genetically modified poplar (Populus spp.)

Abstract

Microbe communities in rhizosphere ecosystems are important for plant health but there is limited knowledge of them in the rhizospheres of genetically modified (GM) plants, especial for tree species. We used the amplitude sequencing method to analyze the V4 regions of the 16S rRNA gene to identify changes in bacterial diversity and community structure in two GM lines (D520 and D521), one non-genetically modified (non-GM) line and in uncultivated soil. After chimera filtering, 468.133 sequences in the domain Bacteria remained. There were ten dominant taxonomic groups (with >1 % of all sequences) across the samples. 241 of 551 genera (representing a ratio of 97.33 %) were common to all samples. A Venn diagram showed that 1.926 operational taxonomic units (OTUs) were shared by all samples. We found a specific change, a reduction in Chloroflexi, in the microorganisms in the rhizosphere soil planted with poplars. Taken together, the results showed few statistical differences in the bacterial diversity and community structure between the GM line and non-GM line, this suggests that there was no or very limited impact of this genetic modification on the bacterial communities in the rhizosphere.