中国生态农业学报2017，Vol.25Issue(3)：410-418,9.DOI:10.13930/j.cnki.cjea.160667
两株解磷细菌的解磷活性及作用机制研究
Phosphate solubilization activities and action mechanisms of two phosphate-solubilizing bacteria
摘要
Abstract
Phosphate-solubilizing bacteria play an important role in increasing soluble phosphorus content in soils and utilization efficiency of phosphatic fertilizers. Halo zone on agar plate was used to screen solubilizing-phosphate bacteria and the molybdenum antimony resistance colorimetric and disodium phenyl phosphate methods were used to analyze solubilizing- phosphate activities and phosphatase activities of the bacteria. The organic acids produced by solubilizing-phosphate bacteria were analyzed using thin layer chromatography (TLC). The taxonomic status of the solubilizing-phosphate bacteria was determined on the basis of physiological and biochemical characteristics and phylogenetic analysis of 16S rRNA gene sequences. The aim of the study was to select bacteria strains solubilizing both inorganic and organic phosphate, and to explore their phosphate solubilization activities and mechanisms. The results showed that two bacteria (designated as JXJ-11 and JXJ-15 strains) exhibited higher activities in solubilizing phytin and the soluble phosphorus contents in the culture broths increased respectively by 219 mg·L-1 and 216 mg·L-1 after three days of incubation. The two strains showed lower activities of solubilizing calcium phosphate and the highest soluble phosphorus contents in the culture broths were only 21.79%–30.37% of phytin in media. Both JXJ-11 and JXJ-15 strains secreted acid, neutral and alkaline phosphatases to degrade insoluble phosphorus and probably produced organic acids (e.g., propionic and succinic acids) which reduced pH values of culture broths while increasing soluble phosphorus contents. Both JXJ-11 and JXJ-15 strains were gram-stain negative, non-endospore forming and positive for the production of hydrogen sulfide. While 16S rRNA gene sequence of JXJ-11 strain was closely related toSphingomonas melonis DAPP-PG 224T andS. aquatilis JSS7T (99.79%), JXJ-15 strain was closely related to Klebsiella pneumoniaesubsp.pneumoniaeDSM 30104T(99.73%). Based on the results above, JXJ-11 and JXJ-15 strains were identified as members of the genusSphingomonas andKlebsiella, respectively. The action mechanisms of phosphate solubilization of JXJ-11 and JXJ-15 strains included secretion of organic acids and phosphatases. The study showed that JXJ-11 strain had a potential application value in developing microbial phosphatic fertilizers.关键词
解磷细菌/解磷活性/有机磷/无机磷/鞘氨醇单胞菌属/克雷白氏杆菌属/16SrRNA基因序列Key words
Phosphate-solubilizing bacteria/Phosphate solubilization activity/Organic phosphate/Inorganic phosphate/Sphingomonas/Klebsiella/16S rRNA gene sequence分类
生物科学引用本文复制引用
陈丹阳,李汉全,张炳火,查代明,杨建远..两株解磷细菌的解磷活性及作用机制研究[J].中国生态农业学报,2017,25(3):410-418,9.基金项目
江西省农业科技支撑计划项目(20121BBF60048)资助 This study was supported by the Agricultural Science and Technology Project of Jiangxi Province (20121BBF60048). （20121BBF60048）
