Abstract: At present, the biological activities of Bacillus.spp and other microorganisms in the acid tea garden soil are not high, thereby difficult to effectively promote plant growth and replace or reduce the usage of chemical fertilizer. In this study, one of Aluminum (Al) tolerance strains, Bacillus subtilis QM7 was isolated from tea garden soil. The auxin (IAA) production of QM7 was influenced by Al concentration (from 85.6 mg·L^-1 to 36.8 mg·L^-1 under 0 to 1 mmol·L^-1 external Al respectively). Results of pot experiment showed that strain QM7 could promote plant growth by increasing root surface area by 56.8% and numbers of root tips by 27.3% in 6 weeks. Two-dimensional gel electrophoresis (2-DE) was used to identify proteins involved in Al toxicity-induced changes. Results showed that more than 64 proteins differentially expressed in response to Al stress, including proteins involved in DNA transcription, protein translation and cell envelope, which reduced the growth of Bacillus subtilis.

Key words: tea planting soil, aluminum tolerance Bacillus subtilis, auxin (IAA), two-dimensional gel electrophoresis