马尾松根际土壤溶磷菌分离筛选、鉴定及其溶磷效果研究

Isolation and Screening,Identification of Phosphorus-solubilizing Bacteria in Rhizosphere Soil of Pinus massonuana and Its Phosphate-degradation Capacity

为了筛选出优良的溶磷菌株,为进一步研制生物复合肥提供基础资料和理论、实践依据,采用NBRIP培养基从马尾松不同林龄根际土壤中分离出具有溶磷能力的菌株431株,不同林龄溶磷菌数量分布有差异,其数量为15年>20年>25年>10年>2年。用溶磷圈法初筛出11株D/d比值较大的菌株,经钼锑抗比色法测定其溶磷量,最后复筛出1株解有机磷能力较强的菌株yL14。结合形态特征、生理生化特性及16S rDNA序列分析表明,yL14菌株属于黄褐假单胞菌(Pseudomonas fulva),该菌溶磷能力达65.14mg/L。试验表明,相对于对照试验培养液的pH值,溶磷菌培养液pH值均略有下降,但是pH值与溶磷量之间无线性关系。该试验获得了溶磷能力较强的菌株,可作为下一步研制生物复合肥的优良菌种。

In order to filter out the fine phosphate-solubilizing strains, for the further development of bio-fertilizer to provide basic information and theoretical and practical basis, 431 phosphorus-solubilizing bacteria were isolated from rhizosphere soil in differrent stand ages of Pinus massonuana sand-fixation forest by NBRIP solid medium. There was different amount of phosphate-solubilizing microorganism in different stand ages of Pinus massonuana sand-fixation forest rhizosphere, the amount in different stand age was in the order： 15 years〉20 years〉25 years〉10 years〉2 years. 11 stains were selected by means of phosphorus hole, their D/d ratio was higher. Phosphorus solubilizing capability of the strains with the molybdenum blue spectrophotometry indicated that yL14 showed stronger ability of dissolving phosphorus, based on the physiological and biochemical characteristics and 16S rDNA sequences, isolate yL14 belonged to the genus Pseudomonas fulva. Its phosphate solubilization capacity was 65.14 mg/L. According to the experiments, there was not directly relationship between the phosphate-dissolving capacity of phosphorus-solubilizing bacteria and the pH reduction of liquid media. The strain could be used as potential strains for biofertilizer manufacture.