毛乌素沙地土壤解磷菌的分离筛选及其解磷机制  

Isolation and screening of soil phosphate-solubilizing bacteria and their phosphate solubilization mechanisms in the Mu Us Desert

作　　者：周晓倩 冯薇[1,2,3] 贺斌 秦树高[1,2,3] 张宇清[1,4,5] ZHOU Xiaoqian;FENG Wei;HE Bin;QIN Shugao;ZHANG Yuqing(Yanchi Research Station,School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;Key Laboratory of National Forestry and Grassland Administration on Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;Engineering Research Center of Forestry Ecological Engineering,Ministry of Education,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Efficient Production of Forest Resource,Beijing Forestry University,Beijing 100083,China;National Engineering Research Center for Tree Breeding and Ecological Restoration,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,宁夏盐池毛乌素沙地生态系统国家定位观测研究站,北京100083 [2]北京林业大学水土保持国家林业和草原局重点实验室,北京100083 [3]北京林业大学林业生态工程教育部工程中心,北京100083 [4]北京林业大学林木资源高效生产全国重点实验室,北京100083 [5]林木育种与生态修复国家工程研究中心,北京100083

出　　处：《农业工程学报》2024年第11期109-118,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(U22A20504,32071844)。

摘　　要：为探究毛乌素沙地土壤中可培养解磷细菌的种类、解磷能力和作用机制,该研究利用磷酸三钙为磷源的培养基,从黑沙蒿(Artemisia ordosica)林地土壤中分离出61株解磷细菌,其中变形菌门(Pseudomonadota)假单胞菌属(Pseudomonas)为优势类群。最终筛选出4株高效解磷菌(命名为R1、R4、NR1和NR3),磷增量分别为501.24、67.78、55.48和800.28 mg/L。基于形态特征、生理生化特性和系统发育分析,鉴定R4和NR1为假单胞菌属,R1和NR3分别为拟无枝酸菌属(Amycolatopsis)和泛菌属(Pantoea)。这些菌株的解磷能力与其分泌的草酸、乙酸、酒石酸量及pH值显著相关。结果表明,具有较强耐盐碱性的4株高效解磷菌,通过分泌有机酸和调节pH值显著提升了有效磷含量,显示出其作为微生物菌剂在干旱地区土壤改良和植被恢复中的潜在应用价值。Phosphate-solubilizing bacteria often transform the insoluble soil phosphorus into the plant-assimilable forms across diverse ecosystems.However,it is still scarce research in desert regions.In this investigation,the soil sample was taken from the predominant sand-fixing shrub community(Artemisia ordosica)in the Mu Us desert.Tricalcium phosphate was employed as the phosphorus medium to selectively isolate the phosphate-solubilizing bacteria,in order to delineate their composition,solubilization capacity,and operative mechanisms.Efficient strains were discerned via halo formation in solid media and liquid culturing,followed by quantification of organic acids,pH levels,and alkaline phosphatase activity within the potent phosphatesolubilizing bacteria cultures.Subsequent morphological,physiological,biochemical,and phylogenetic analyses were carried out for the precise characterization and identification of efficient strains.Pearson correlation analysis was used to elucidate the interplay between phosphate solubilization capacity and the culturing environment.The results are as follows:1)A total of sixty-one strains of phosphate-solubilizing bacteria were isolated from both rhizosphere and non-rhizosphere soil of Artemisia ordosica,belonging to three phyla and five genera.Among them,Pseudomonas had the highest isolation rate(80.33%),followed by Streptomyces(11.47%).2)Only seven strains(named R4,R5,R6,R7,NR1,NR2,and NR3)were produced in the transparent halos,with NR3 at the largest ratio of halo diameter to colony diameter.3)There was an effective phosphorus increment of the seven strains with transparent halos after seven days of liquid culture.Three additional strains(named R1,R2,and R3)without transparent halos had better growth in the range from-5.40 to 800.28 mg/L.Specifically,four strains(R1,R4,NR1,and NR3)demonstrated phosphorus increments of 501.24,67.78,55.48,and 800.28 mg/L,respectively,indicating the efficient phosphate-solubilizing bacteria.4)All four strains were growing on a medium with a pH of 11 and a

关 键 词：解磷细菌 溶磷能力 无机磷 有机酸 毛乌素沙地 

分 类 号：S154.39[农业科学—土壤学]