Feng Zengwei, Gao Hong, Ding Ling, Qin Yongqiang, Zhou Yang, Feng Guangda, Yao Qing, Zhu Honghui
Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China.
Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China; Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, China.
Environ Res. 2025 Feb 1;266:120599. doi: 10.1016/j.envres.2024.120599. Epub 2024 Dec 14.
Phosphate mobilising bacteria (PMB), such as phoD- and pqqC-harbouring bacteria, play a crucial role in mobilising insoluble phosphorus (P) in soil through the secretion of alkaline phosphatase and organic acids.
To evaluate the succession pattern of PMB communities in response to different insoluble P sources.
Five P source treatments, including the addition of KHPO (PDP), FePO (FEP), Ca(PO) (TCP), lecithin (LEC), and a negative control, were established in the soil in a microcosmic system. Subsequently, phoD- and pqqC-harbouring bacterial communities were investigated by sequential sampling and high-throughput sequencing. In addition, PMB strains were isolated from these five treatments, and their phosphate mobilising activity was further analysed.
The effect of the insoluble organic P source (LEC) on the succession of PMB communities consistently exceeded that of insoluble inorganic P (Pi) sources (FEP and TCP). A successively enhanced succession and a successively diminishing succession were observed in PMB communities in FEP and TCP, respectively. Furthermore, the soil AP content significantly increased with incubation time in LEC and FEP. Most of the variation in phoD- and pqqC-harbouring bacterial communities was explained by all P fractions, respectively, while Fe-P and stable organic P fractions determined the PMB communities. Insoluble Pi sources, particularly FEP, tended to enrich more high-performance PMB strains for Fe-P.
This study firstly reveals the dynamic response of PMB communities to different insoluble P sources at the community level in a short time scale and identifies key PMB taxa that respond to different insoluble P sources, particularly Fe-P. It is also the first to provide community evidence and a feasible method for obtaining high-performance PMB strains for Fe-P in subtropical acidic red soils through directed enrichment culture.
磷活化细菌（PMB），如携带phoD和pqqC的细菌，通过分泌碱性磷酸酶和有机酸在土壤中难溶性磷（P）的活化过程中发挥关键作用。
评估PMB群落对不同难溶性磷源的演替模式。
在微观系统的土壤中设置了五种磷源处理，包括添加KHPO（PDP）、FePO（FEP）、Ca(PO)（TCP）、卵磷脂（LEC）以及一个阴性对照。随后，通过连续采样和高通量测序研究了携带phoD和pqqC的细菌群落。此外，从这五种处理中分离出PMB菌株，并进一步分析它们的磷活化活性。
难溶性有机磷源（LEC）对PMB群落演替的影响始终超过难溶性无机磷（Pi）源（FEP和TCP）。在FEP和TCP处理的PMB群落中分别观察到演替依次增强和依次减弱的情况。此外，在LEC和FEP处理中，土壤有效磷含量随培养时间显著增加。携带phoD和pqqC的细菌群落的大部分变异分别由所有磷组分解释，而铁磷和稳定有机磷组分决定了PMB群落。难溶性Pi源，特别是FEP，倾向于富集更多用于铁磷的高性能PMB菌株。
本研究首次在短时间尺度上揭示了PMB群落在群落水平上对不同难溶性磷源的动态响应，并确定了对不同难溶性磷源，特别是铁磷作出响应的关键PMB分类群。这也是首次通过定向富集培养为亚热带酸性红壤中获取用于铁磷的高性能PMB菌株提供群落证据和可行方法。
