Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Rep. 2017 Feb 9;7:42284. doi: 10.1038/srep42284.
Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance of pqqC gene (pqqC/16S). The decreased iPSB abundance was strongly related to pH decline and total N increase, revealing that the long-term N additions may cause pH decline and subsequent P releases relatively decreasing the demands of the iPSB community. The methodology and understanding obtained here provides insights into the ecology of inorganic P solubilizers and how to manipulate for better P use efficiency.
解磷细菌（iPSB）对于促进碱性土壤中磷（P）的活化至关重要，但 iPSB 群落的系统发育结构仍未得到很好的描述。因此，我们使用参考 iPSB 数据库，基于 16S rRNA 基因 illumina 测序来分析 iPSB 群落的分布。此外，还开发了一种新的 pqqC 引物来定量 iPSB 的丰度。在本研究中，选择了一种具有 27 年施肥处理的碱性土壤。iPSB 的比例为每个样本的 1.10%~2.87%，优势 iPSB 属与节杆菌属、芽孢杆菌属、短杆菌属和链霉菌属密切相关。长期 P 施肥对 iPSB 群落的丰度没有显著影响。与 P 和 K 添加不同，长期 N 施肥会降低 iPSB 的丰度，这可以通过 pqqC 基因（pqqC/16S）的相对丰度降低来验证。iPSB 丰度的降低与 pH 值下降和总氮增加密切相关，表明长期 N 添加可能导致 pH 值下降，随后 P 释放相对减少，从而降低 iPSB 群落的需求。这里获得的方法和理解为了解无机 P 溶解菌的生态学以及如何操纵它们以提高 P 利用效率提供了思路。
