| In order to develop and utilize the saline-alkali microorganisms and provide germplasm resources for promoting crop stress growth. In this study, salt-tolerant strains were isolated and screened from saline-alkali soil in the Manas River Basin of Xinjiang. By measuring the growth characteristics of the strain and the ability to produce acetic acid(IAA), iron carrier, phosphorus solubilization and nitrogen fixation, one salt-tolerant and high-efficiency was determined. The strain wp-8 was combined with morphological observation, physiological and biochemical and 16S rDNA to identify its species. The pot experiment was carried out by indoor salt stress wheat pot experiment. The results showed that the optimum growth temperature of strain wp-8 was 30 °C, the optimum growth pH was 9, the optimum growth salinity was 5%, the indole acetic acid secretion was 15.90 mg·L-1, and the relative content of iron carrier was 0.68. The dissolved organic phosphorus and inorganic phosphorus were 0.34 mg·L-1and 1.10 mg·L-1, respectively, and the strain was identified as Nesterenkonia rhizosphaerae. Under the stress of 150 mmol·L-1NaCl, the wheat seeds were inoculated with wp-8. After 50 days of growth, the plant height, root length and root fresh weight were significantly increased compared with the control(P<0.05). The rates were 9.35%, 27.15% and 150%, respectively. The fresh weight increased from 0.82 g to 1.01 g, an increase of 23.17%, but the difference was not significant.In addition, inoculating strain wp-8 significantly reduced the content of malondialdehyde(MDA) in roots of wheat seedlings(P<0.05), and increased superoxide dismutase(SOD), peroxidase(POD),catalase(CAT) activity and leaf proline(Pro) content, respectively 160.63%, 30.41% ,44.93%,10.04% higher than control, and the difference reached a significant level(P< 0.05 ). It indicated that strain wp-8 can alleviate the salt stress of wheat and promote the growth of seedlings, especially the development of roots. |
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