Abstract:

Rhizosphere microorganisms have great effects on plant growth and development. The exudates of plants can also affect the distribution and species of microorganisms in rhizosphere. In this study，a high throughput sequencing technology was used to clarify the effects of MdSOS2L1 transgenic Gala apple plants on rhizosphere microorganisms. The results showed that there were great differences in the abundance and diversity of rhizosphere microorganisms among the MdSOS2L1 transgenic apple plants in compared with wild type apple plants. Among them，the rhizosphere of prokaryote community varied obviously in phylum level. The abundance of Acidobacteria in transgenic apple rhizosphere was higher than that in wild type apple plants. The abundance of Cyanobacteria and Actinobacteria was lower in transgenic apple rhizosphere microorganisms. Meanwhile，the pH value of rhizosphere soil of transgenic plants was lower than that of wild type plants. And the contents of oxalic acid，citric acid and L-malate in transgenic plants root were higher than that in wild type plants rhizosphere soil，but no significant differences occurred among the bulk soil between these two types of apple plants. Above of all，it is suggested that the MdSOS2L1-mediatedsecretion of organic acids contributes to the difference in rhizosphere microorganisms.

Key words: apple, MdSOS2L1, rhizosphere microbial diversity, high throughput sequencing, organic acids