一株溶磷抑病细菌的筛选及其溶磷特性

【目的】筛选一株兼具高效利用Ca3(PO4)2、磷矿粉和卵磷脂等难溶性磷源和抑制土传病害功能的菌株。【方法】液体培养条件下测定所筛菌株对Ca3(PO4)2、磷矿粉和卵磷脂的溶磷效果,平板对峙试验研究对土传病害的拮抗作用。【结果】通过室内平板和摇瓶试验,从江苏和安徽的5种石灰性土壤中分离、筛选获得的6株溶磷菌,均能溶解Ca3(PO4)2、磷矿粉和卵磷脂。其中,菌株P1溶解Ca3(PO4)2和卵磷脂的效果最好,培养7d后水溶性磷浓度分别达到674.5和33.0μg·mL-1,其对磷矿粉的溶磷量也达132.3μg·mL-1。经过16SrDNA基因序列分析和生理生化鉴定,菌株P1为唐菖蒲伯克霍尔德氏菌。对峙试验结果表明,其对辣椒疫霉、大丽轮枝菌、烟草疫霉烟草变种和立枯丝核菌都有一定的拮抗作用。【结论】菌株P1不仅对Ca3(PO4)2、磷矿粉和卵磷脂有较好的溶解效果,对一些土传病害病原菌也有抑制作用。

Screening of a Phosphate Solubilizing and Disease Inhibiting Bacteria Strain and Studies on Its P-Solubilizing Characteristics

【Objective】 The aim of the experiment was to isolate a strain solubilizing various forms of insoluble-phosphate such as tricalcium phosphate, rock phosphate and lecithin and having antagonism reaction against soil borne diseases. 【Method】 Liquid culture medium was used to measure P-solubilizing activities of tricalcium phosphate, rock phosphate and lecithin and an in-door plate antagonism experiment was conducted to study its antagonistic activities against soil borne disease. 【Result】 Six strains solubilizing tricalcium phosphate, rock phosphate and lecithin were isolated from five calcareous soils collected from Jiangsu and Anhui provinces by plate and broth assay. Strain P1 was the most effective for solubilizing tricalcium phosphate and lecithin after 7 days cultivation, with water-soluble phosphorus (WPS) concentration in the culture up to 674.5 μg?mL-1and 33.0 μg?mL-1, respectively, and strain P1 could also effectively solubilize rock phosphate with WSP concentration up to 132.3 μg?mL-1. After physiological characteristics identification and 16S ribosomal DNA gene sequence analysis, strain P1 was identified as Burkholderia gladioli. In addition, the results of plate antagonistic experiment showed that strain P1 had strong antagonistic activities against Phytophthoia capsici, Verticillium dahliae, Phytophthora parasitica var. nicotianae and Rhizoctonia solani. 【Conclusion】 Strain P1 could both effectively solubilize tricalcium phosphate, rock phosphate and lecithin and have antagonistic ability against several soil-borne pathogens.