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[Objective]A rhizobacterium with salt-resistant and growth-promoting effects was screened from the saline-alkali soil in Yellow River Delta to prepare an agent for alleviating high-salt stress of maize seedlings.[Method]The salt-resistant and growth-promoting functions of the strain were identified on functional mediums, and the species of the strain was determined by 16S rDNA sequence and whole genome analysis. The strain was applied to maize rhizosphere to verify the salt-resistant and growth-promoting effects of the strain on maize seedlings.[Result]A strain Bacillus atrophaeus CNY01 was screened from the saline-alkali soil of Yellow River Delta. Strain CNY01 grew normally under the condition of 0-16% NaCl and pH 5-8. Strain CNY01 had the ability of degrading protein and dissolving potassium, and inhibited the growth of plant pathogens such as Ralstonia solanacearum and Fusarium moniliforme. The application of strain CNY01 promoted the growth of maize seedlings under high-salt condition and alleviated the stress of high salt on maize seedlings. When strain CNY01 was applied to maize seedlings in nutrient solution containing 100 mmol/L NaCl for 8 d, the physiological plant height, root length, and fresh weight of maize seedlings increased by 38.80%(P<0.01), 23.73%, and 28.19%(P<0.01), respectively. When strain CNY01 was applied to maize seedlings in pot experiments adding 100 mmol/L NaCl for 28 d, the physiological plant height, the aboveground fresh weight, and the underground fresh weight of maize seedlings increased by 10.84%, 41.87%(P<0.01), and 23.29%, respectively. Genes that maintain cell osmotic pressure and synthesize stress proteins to alleviate high salt stress were also predicted in the genome sequence of this strain.[Conclusion]A strain of B. atrophaeus CNY01 is screened from saline-alkali soil of Yellow River Delta, which has the function of preventing disease and promoting growth, and has significant salt-resistant and promoting growth effect on maize plants. Meanwhile, strain CNY01 contains genes related to salt-resistant and growth-promoting. B. atrophaeus CNY01 is an important strain resource. [ABSTRACT FROM AUTHOR]