磷铁尾矿中高效解磷菌筛选、鉴定及解磷特性

Isolation,identification and phosphate solubilizing characteristics of a phosphate solubilizing bacterium from ferrophosphate tailings

【目的】从磷铁尾矿矿泥中筛选到高效解磷微生物,并评价其解磷效果与促进生菜生长的能力。【方法】采用无机磷选择性培养基和国际植物研究所磷酸盐生长培养基(NBRIP),进行解磷菌的初筛与复筛;利用形态、分子和生理生化鉴定,明确目标菌株分类地位;利用不同Ca_(3)(PO_(4))_(2)添加量和不同培养时间液体发酵试验,评估目标菌株解磷效果;利用平板促生长试验,测定目标菌株对生菜的促生长效果。【结果】初筛获得19株菌,复筛后确定JP21-05菌株为目标解磷菌株,JP21-05菌株与人参假单胞菌Pseudomonas panacis(MT033062.1)16S rRNA基因相似性为100.00%,结合形态、生理生化特征,确定其为人参假单胞菌。添加7 g/L Ca_(3)(PO_(4))_(2)的NBRIP液体培养5 d,JP21-05菌株解磷能力最强,可溶性磷(PO^(3-)_(4))浓度为45.94 mg/L。JP21-05菌株对生菜具有显著的促生长作用,能够促进生菜侧根生长,提高了地上和地下部分鲜重。【结论】从磷铁尾矿中分离获得1株具有解磷活性的人参假单胞菌,对生菜具有促生长作用。

[Objective]In the present study,we focused on the screening of high-efficiency phosphorus solubilizing microorganisms(PSM)from ferrophosphate tailings slime,and evaluating their phosphate solubilizing effect and promoting plant growth promoting ability towards lettuce[Methods]Inorganic phosphorus selective medium and National Botanical Research Institute's Phosphate(NBRIP)medium were used to screen and rescreen of PSM.Systematic classification was determined based on morphological,molecular,physiological and biochemical identification.Liquid fermentation experiments with different amounts of Ca_(3)(PO_(4))_(2) and different culture time were performed to evaluate the phosphorus solubilization capacity of the target strain.The growth promoting ability of the target strain towards lettuce was determined by plate growth promoting experiment.[Results]Nineteen candidate strains were obtained by screening,subsequently,strain JP21-05 was determined to be the target PSM strain by rescreening.The target strain demonstrated 100%similarity of 16S rRNA gene with that of Pseudomonas panacis(MT033062.1).It was further determined to be P.panacis combining with the results of morphological,physiological and biochemical characteristics.After 5-day’s liquid fermentation using NBRIP medium with 7 g/L Ca_(3)(PO_(4))_(2),strain JP21-05 manifested the highest phosphorus solubilization capacity of 45.94 mg/L.The strain JP21-05 demonstrated significant promoting activity towards lettuce.It promoted the growth of lateral roots,and improved the fresh weight of aboveground and underground parts.[Conclusion]A PSM strain P.panacis was isolated from ferrophosphate tailings,which can promote the growth of lettuce.