荒漠草原植物根际溶磷细菌的分离鉴定及其溶磷能力的比较

Isolation, Characterization and Phosphate-solubilizing Ability Determination of Phosphate-solubilizing Bacteria from the Rhizobacteria of Dominant Plants in Desert Steppe

溶磷细菌是主要的根际促生菌的类群之一,其在发展绿色农业和荒漠化防治中具有重要作用。已有的相关研究主要集中于农作物等,而对于荒漠草原植物溶磷细菌的研究尚很缺乏。该研究利用涂布划线方法、以无机磷培养基从四子王旗荒漠草原四种优势植物根际土壤中分离溶磷细菌,采用过硫酸钾消解-钼锑抗比色法检测菌株的溶磷能力。从4种优势植物兔唇冬青草、银灰旋花、蒙古黄芪和短花针茅根际土壤共分离得到42株溶磷细菌,归为五个类群19个属。其中19株(45.2%)属于放线菌纲(Actinobacteria),5株(11.9%)属于芽孢杆菌纲(Bacilli),16株(38.1%)属于α-变形菌纲(α-proteobacteria),1株(2.4%)属于β-变形菌纲(β-proteobacteria),1株(2.4%)属于γ-变形菌纲(γ-proteobacteria)。溶磷能力测定结果表明菌株GP0501、GP0506、GP0507和GP0509在42株菌种中溶磷能力最强,溶磷量分别为77.57、65.89、58.08、68.02μg/mL,都属于芽孢杆菌属(Bacillus),具有较大的应用潜力。

As one of the major groups of plant growth-promoting bacteria,phosphate-solubilizing bacteria play an important role in the development of green agriculture and control of desertification.The present research mainly focus on phosphate- solubilizing bacteria of farmland,classic grassland and desert ecosystem,however plant growth-promoting rhizobacteria of desert steppe has rarely been studied.The phosphate-soiubilizing bacteria were isolated by the insoluble phosphate medium, and the phosphate-solubilizing ability of the isolates were detected by the potassium persulfate digestion and Mo-Sb anti colorimetric method.42 phosphate-solubilizing bacteria were isolated from the rhizosphere of four dominant plants in desert steppe of Siziwang Banner.The 42 strains were classified into 5 groups and 19 genuses.Among them,19 isolates （45.2%） belong to the Actinobacteria,5 strains （11.9%） belong to the Bacilli,16 strains （38.1%） belong to α-proteobacteria,1 strain （2.4%） belong to β- proteobacteria,and 1 strain （2.4%） belong to γ-proteobacteria.The results showed that strain GP0501,GP0506,GP0507 and GP0509 have the strongest phosphate solubilizing ability,the phosphate solubilization capacity was 77.57,65.89,58.08,68.02g/μ mL,respectively.The 4 strains have great potential of application,which all belong to Bacillus.