毛竹根际解磷菌木糖氧化无色杆菌的分离及其解磷机制  

Isolation and phosphorus-solubilizing mechanism of Achromobacter xylosoxidans in the rhizosphere of Moso bamboo

作　　者：项春铸 房翠莲 田佳怡 张清 李全 宋新章[1] 曹婷婷 XIANG Chunzhu;FANG Cuilian;TIAN Jiayi;ZHANG Qing;LI Quan;SONG Xinzhang;CAO Tingting(Bamboo Industry Institute,Zhejiang A&F University,State Key Laboratory of Subtropical Silviculture,Hangzhou,Zhejiang,China)

机构地区：[1]浙江农林大学竹子研究院,亚热带森林培育国家重点实验室,浙江杭州

出　　处：《微生物学报》2025年第2期614-628,共15页Acta Microbiologica Sinica

基　　金：国家自然科学基金(32125027,32301674,31930075);浙江省自然科学基金(LQ24C160005,LQ23C160006);浙江农林大学人才启动项目(2022LFR006,2022LFR106)。

摘　　要：【目的】分离毛竹(Phyllostachys edulis)根际兼备溶解无机磷和有机磷能力的菌株,挖掘菌株解磷相关的功能基因,为利用解磷微生物活化土壤磷库、提高土壤磷有效性奠定基础。【方法】以亚热带地区重要经济林木——毛竹为研究对象,采用高通量筛选技术分离毛竹根际解磷菌。通过微孔板培养和土壤接种实验,分别探究碳源类型和土壤磷含量对其解磷能力的影响。采用全基因组测序技术解析其与解磷相关的基因,以探究其解磷机制。【结果】筛选出一株多途径解磷的细菌,命名为zafu-3,鉴定为木糖氧化无色杆菌(Achromobacter xylosoxidans)。该菌株能利用葡萄糖和柠檬酸等4种碳源来溶解Ca3(PO4)2、Fe PO4、AlPO4、卵磷脂和植酸钙,最佳解磷效果为32.75 mg/(L·d)。与对照组相比,接种菌株zafu-3后,土壤酸性和碱性磷酸酶活性分别增加了4.21%-33.88%和13.54%-112.06%,特别是在高磷土壤中,土壤pH值降低了0.04,有效磷含量增加了16.32%。全基因组结果表明,该菌株包含了35个参与磷酸水解酶编码的基因和53个参与有机酸代谢的编码基因。此外,菌株zafu-3具有产生产吲哚乙酸、铁载体和降解木质素的相关功能基因。【结论】菌株zafu-3可通过分泌多种有机酸和磷酸酶直接溶解无机和有机磷源,并可能通过促进植物生长间接激活土壤磷库,这为多功能生物肥料的开发提供了重要的菌种资源和科学依据。[Objective]To isolate the strain for solubilizing both inorganic and organic phosphorus(P)from the rhizosphere of Moso bamboo(Phyllostachys edulis)and mine the related genes,laying a foundation for activating the soil P pool and improving P bioavailability by P-solubilizing microorganisms(PSM).[Methods]High-throughput screening was employed to isolate PSM strains from the rhizosphere of Moso bamboo,an important economic plant in subtropical regions.The P-solubilizing activities of the strain under various carbon sources and soil P levels were investigated by microplate culture and soil inoculation experiments,respectively.The genes involved in P solubilizing of the strain were mined by whole-genome sequencing.[Results]The strain zafu-3(Achromobacter xylosoxidans)capable of solubilizing P via multiple pathways was isolated from the rhizosphere of Moso bamboo.The strain solubilized Ca3(PO4)2,FePO4,AlPO4,lecithin,and calcium phytate by using four carbon sources such as glucose and citric acid,with the highest P-solubilizing activity of 32.75 mg/(L·d).Compared with the control group,the zafu-3inoculation group showed increases of 4.21%-33.88%and 13.54%-112.06%in activities of acid phosphatase and alkaline phosphatase,respectively.In the high P-level soil,inoculation of the strain decreased the soil pH by 0.04 and increased the available P content by 16.32%.The whole genome of strain zafu-3 contained 35 genes encoding phosphohydrolases and 53 genes involved in organic acid metabolisms.Furthermore,strain zafu-3 carried the genes associated with the production of indole-3-acetic acid and siderophores,and the degradation of lignin.[Conclusion]Strain zafu-3 directly solubilized inorganic and organic P by secreting diverse organic acids and phosphatases,and indirectly activated soil P pools by promoting plant growth.These findings provide an important microbial resource and theoretical foundation for the development of multifunctional biofertilizers.

关 键 词：毛竹 木糖氧化无色杆菌 解磷菌 土壤磷动员 基因组 

分 类 号：S714.3[农业科学—林学]