一株溶磷真菌的分离鉴定及其溶磷能力的初步研究

Phosphate-solubilizing Mechanism of PSFM and Preliminary Study on Solubilization Capacity of Insoluble Phosphates

利用有机磷液体培养基进行生物富集,无机磷固体培养基平板稀释法进行分离筛选,分离到一株具有溶磷能力的菌株PSFM,经过形态观察和核糖体间隔区ITS扩增序列分析,确定该菌株为黑曲霉(Aspergillus niger)。以Ca3(PO4)2为唯一磷源的液体培养基接种参试菌株PSFM,在28℃,180r/min条件下通过不同时间取样测定培养液的pH、速效磷含量,同时研究溶磷真菌PSFM的生长动态及在固体平板上的溶磷能力。结果表明,PSFM菌株具有高效溶磷能力,培养144 h溶磷量达到511.28 mg/L,继续培养菌株溶磷能力降低;溶磷菌株的培养液中pH值随溶磷量的增大而下降,在144 h时该培养液的pH值降到2.03,以后仍继续保持在低pH值水平。对供试菌株PSFM的生长曲线研究发现其在第6天时菌丝体重量达到最大值。

One phosphorus solubilizing fungal strain named PSFM was isolated by biological enriching using organic phosphobacteria liquid medium and then screened via plate dilution method using inorganic phosphofungi solid medium. It was identified as Aspergillus niger by means of morphological observation and ribosomal spacers ITS amplified sequence analysis. The tested strain PSFM was evaluated in liquid medium containing Ca3（PO4）2 as the only P source under temperature 28% and shaking speed 180 r/min in different time and on solid plate .The results showed that, It was found that tbc phosphorus solubilizing fungal strain had strong capacity to solubilize phosphate. In liquid culture, the strain PSFM had a dissolving phosphorus capacity of 511.28mg/L in the frist 14gh, and the capacity descended with continuing culture. The changes in pH value and in phosphor content were determined when the strain was grown in liquid medium cultures, The pH would decrease to 2.03 after 144 h culture and continue to maintain a low level. Its growth curve was studied and it was found that the mycelium was the maximum when shaking culture was for 6 d.