Abstract: ObjectiveThe strains with sound phosphate solubilizing capacity were isolated from rhizosphere soil of Rhodiola fastigiata in Sehgyla Mountains in Tibet,and their taxonomic status,growth promoting effects and low tempera-ture adaptation were introduced to provide theoretical basis and reference for developing growth promotion rhizobacteria of psychrophytes and enriching phosphate solubilizing strain resources.MethodR.fastigiata was research species.Phos-phate solubilizing ring method was applied to isolate phosphate solubilizing bacteria,and the method of Mo-Sb colorime-try was applied to measure phosphorus solubilizing capacity.The strains with the optimum phosphorus solubilizing capaci-ty were selected,and their abilities of indoleacetic acid(IAA)production,nitrogen fixation and growth promotion were evaluated.These strains were graded based on morphology,physiological-biochemical characteristics and 16S rRNA gene sequence.Bacillus subtilis was used as control.B.subtilis and the strains isolated were cultured at 4,10,15,20 and 30℃for 7 d to study their low temperature adaptability.ResultFrom the rhizosphere soil of Rhodiola fastigiata,21 bacterial strains with inorganic phosphate solubilizing capacity were selected.Phosphate solubilizing diameter/colony diameter(D/d) value of PSB19 was the highest in PKO liquid culture medium,and soluble phosphorus content reached 392.15 mg/L. PSB19 had ability of IAA secretion,nitrogen fixation,and grew well under low temperature(4 and 10℃). Through mor-phology,physiology and biochemistry identification and 16S rDNA sequence analysis,strain PSB19 was classified as En-sifer adhaerens.ConclusionStrain PSB19 has sound phosphate solubilizing capacity,IAA production,nitrogen fixation and low temperature adaptation.Therefore,it might act as a biological bacterial fertilizer for the application in agricultural production and revegetation.