摘要
土壤有效磷匮乏是制约毛竹林生产力和生态功能发挥的关键因素,挖掘其根际解磷菌资源、探究菌株解磷机制是绿色、高效培育毛竹林的重要策略。本研究采用高通量筛选方法分离毛竹根际解磷菌,探究其在15种碳源下的解磷效果,采用全基因测序技术分析菌株参与磷循环的相关基因,通过接种试验探究菌株对长期磷添加(100 kg P·hm^(-2)·a^(-1))土壤磷的溶解能力。从毛竹根际分离出一株高效解磷细菌zafu-111,经鉴定为洋葱伯克霍尔德菌。该菌株主要利用葡萄糖和柠檬酸等4种碳源溶解3种无机磷(磷酸三钙、磷酸铁、磷酸铝)和2种有机磷(卵磷脂和植酸钙),解磷能力最高为54.55 mg·L^(-1)·d^(-1)。菌株zafu-111具有无机磷溶解、有机磷矿化、磷转运和磷饥饿调控4类参与土壤磷循环的功能基因,gltA和ppa等41个有机酸代谢的编码基因和phoA、phoD等45个调控磷酸酶合成的基因。此外,菌株zafu-111具有产吲哚乙酸(IAA)、分泌铁载体、降解木质素和分解硅酸钙的能力。接种30 d后,菌株zafu-111使对照样地土壤酸性磷酸酶提高34.4%,有效磷含量增加21.6%;在磷添加样地二者则分别降低5.9%和6.8%。接种90 d后,对照样地土壤pH提高0.03个单位,有效磷含量无显著变化;而磷添加样地土壤的pH提高0.06个单位,有效磷含量提高35.4%。综上,菌株zafu-111可利用多种碳源提高难溶性磷的溶解,同时具备丰富的植物促生功能基因及相关特性,在缓解毛竹林磷胁迫及微生物菌肥开发中具有重要潜力。
The deficiency of soil available phosphorus(P)is a key factor restricting the productivity and ecological function of Moso bamboo(Phyllostachys edulis)forest.It is thus important to explore the resources of rhizosphere P-solubilizing bacteria(PSB)and their solubilizing mechanisms for green and efficient cultivation of Moso bamboo forest.In this study,we isolated PSB from the rhizosphere using high-throughput screening method,and investigated its P-solubilizing activity under various carbon sources.We analyzed the genes involved in P cycling by whole-genome sequencing technology.An inoculation experiment was conducted to explore the P-solubilizing ability of the strain in soils with long-term P addition(100 kg P·hm^(-2)·a^(-1)).The highly efficient P-solubilizing bacterium,zafu-111,isolated from the rhizosphere,was identified as Burkholderia cepacia.The strain mainly utilized four kinds of carbon sources,such as glucose and citric acid to dissolve three inorganic P(Ca_(3)(PO_(4))_(2),FePO_(4),AlPO_(4))and two organic P(lecithin and calcium phytate),with a maximum activity of 54.55 mg·L^(-1)·d^(-1).The strain zafu-111 possessed four categories of functional genes involved in soil P cycling,such as inorganic P solubilization,organic P mineralization,P transportation,and P starvation regulation.The strain contained 41 coding genes for organic acid metabolism(such as gltA and ppa)and 45 genes regulating phosphatase synthesis(including phoA and phoD).Additionally,strain zafu-111 could produce IAA,secrete siderophores,decompose lignin and calcium silicate.After 30 d inoculation,strain zafu-111 increased acid phosphatase activity by 34.4% and elevated available P content by 21.6% in the control,but decreased both by 5.9% and 6.8% in the P addition group.After 90 d inoculation,soil pH in the control increased by 0.03 units with no significant change in available P content;P addition increased pH by 0.06 units and available P by 35.4%.Overall,strain zafu-111 improved the dissolution of insoluble P through utilizing various carbon sources,and possessed abundant functional genes and traits associated with plant growth-promoting.These characteristics of strain provide significant potential for alleviating P stress in Moso bamboo forests and developing microbial fertilizers.
作者
房翠莲
曹婷婷
尹语申
胡昊鸿
邹程康
郑邹程
李全
宋新章
FANG Cuilian;CAO Tingting;YIN Yushen;HU Haohong;ZHOU Chengkang;ZHENG Zhoucheng;LI Quan;SONG Xinzhang(National Key Laboratory for Development and Utilization of Forest Food Resources,Zhejiang A&F University,Hangzhou 311300,China;Key Laboratory of Bamboo Science and Technology of Ministry of Education,Bamboo Industry Institute,Zhejiang A&F University,Hangzhou 311300,China)
出处
《应用生态学报》
北大核心
2025年第10期3175-3186,共12页
Chinese Journal of Applied Ecology
基金
浙江省自然科学基金项目(LQ24C160005,LQ23C160006)
国家自然科学基金项目(32125027,32301674)
浙江农林大学人才启动项目(2022LFR006,2022LFR106)资助。
关键词
毛竹
伯克霍尔德菌
解磷菌
土壤磷活化
基因组
Moso bamboo
Burkholderia
phosphorus-solubilizing microorganism
soil phosphorus mobilization
genome
