一株溶磷细菌的分离、鉴定及其溶磷特性研究

Studies on Phosphorus Solubilizing Activity of a Strain Isolated from Corp Rhizosphere

从作物根际土壤样品中筛选到一株溶P能力强的菌株GJT-1,结合生理生化指标和16SrDNA序列分析鉴定其为假单胞菌(Pseudomonas sp.)。菌株GJT-1对磷酸三钙、磷酸铝、磷酸铁有一定的溶解能力,28℃培养到第3天对磷酸三钙液体培养基的溶P量可达224.51mg/L。该菌对开阳磷矿粉和宜昌磷矿粉的溶P量分别为194.25mg/L和120.59mg/L。通过扫描电镜观察到接种活菌处理的磷矿粉表面凹凸且有黏性物质附着,表明菌株GJT-1可利用磷矿粉。

Phosphobacterium GJT-1 was isolated from the rhizosphere of crop and was identified as Pseudomonas sp., based on its physiological characteristics and 16S rDNA sequence analysis. Phosphate-dissolving activity was measured in solid media as well as in liquid media using different phosphate sources including tricalium phosphate, aluminium phosphate, ferric phosphate. When phosphobacterium GJT-1 was inoculated into NBRIP liquid culture, the release of maximal available soluble phosphorus reached to 224.51 mg/L after 3 days incubation at 28℃. The strain showed high phosphate-dissolving activity for rock phosphates from Kaiyang in Guizhbu Province and Yichang in Hubei Province with the capacity of 194.25 mg and 120.59 mg soluble phosphate respectively per liter medium. SEM study of the phosphorite powders retrieved from the phosphobacterium GJT-1 cultured medium revealed the actual dissolution of phosphate from the mineral surface.