the NationalThe Natural Science Foundation of China and the National Key Research and Development Program of China
水稻土氧化还原交替频繁，使不同形态的硫元素转化的生物化学反应活跃，对水稻生产影响显著。本文以花岗岩和第四纪红色黏土母质发育的红壤性水稻土为研究对象，通过宏基因组测序以及生物信息学分析，研究了红壤性水稻土硫循环途径相关功能微生物特征，包括有机硫转化途径、其他（转运）途径、同化硫酸盐还原途径、硫氧化途径、异化硫酸盐还原途径以及硫歧化途径。结果表明：两种母质发育的红壤性水稻土具有相同的硫循环途径特征，即有机硫转化途径微生物功能基因丰度的发生频率最高，每百万个带注释的细菌序列平均检测到16000个有机硫转化的功能基因；硫歧化途径微生物功能基因丰度的发生频率最低，每百万个带注释的细菌序列平均仅检测到116个硫歧化途径功能基因。两种母质发育的红壤性水稻土中主导硫循环的微生物，在门分类水平上，微生物组成没有显著差异，都以变形菌门（Proteobacteria）、酸杆菌门（Acidobacteria）、绿弯菌门（Chloroflexi）为优势菌门，占比分别为55.19%、10.61%、7.18%等。在种水平分类上则差异显著，花岗岩母质发育的水稻土中硫循环途径微生物相对丰度更高，且所有途径的优势菌种都为Deltaproteobacteria bacterium、Acidobacteria bacterium、Betaproteobacteria bacterium，其丰度占花岗岩母质水稻土硫循环微生物丰度的40%以上；而在第四纪红色黏土母质发育的水稻土中参与硫循环每条途径的优势功能微生物更加丰富，如在有机硫转化途径中Gemmatirosa kalamazoonesis丰度最高，在其他（转运体）途径Azoarcus sp.的丰度最高，在同化硫酸盐还原途径丰度最高的微生物是Anaeromyxobacter sp.。研究结果表明：两种不同母质发育的红壤性水稻土中存在相同的硫循环途径特征，两种母质发育的红壤性水稻土中主导硫循环的微生物在门水平上没有显著差异，但在种水平分类上差异显著，表明不同母质中会存在着独特的优势硫转化功能菌群。
Abstract:【Objective】The frequent redox alternations in paddy soils make the biochemical reactions of different forms of sulfur active, which has a significant influence on rice production.【 Method】This study aimed to explore the characteristics of sulfur cycling pathways in red paddy soils with different parent materials. Also, the influence of parent materials on the characteristics of sulfur cycling pathways, sulfur metabolizing microorganisms, and the main functional microbial communities responsible for each sulfur cycling pathway; including the organic sulfur transformation pathway, other (transfer) pathway, assimilate sulfate reduction pathway, sulfur oxidation pathway, alienation sulfate sulfur reduction approach and disproportionation.【Result】The two kinds of parent material developed red paddy soils had the same characteristics of the sulfur cycle pathway. The frequency of microbial functional gene abundance in the organic sulfur transformation pathway was the highest, with an average of 16,000 organic sulfur transformation functional genes detected per million annotated bacterial sequences. Also, the frequency of the abundance of sulfur disambiguation pathway functional genes was the lowest, and only 116 genes were detected per million annotated bacterial sequences. At the level of phylum classification, there was no significant difference in the composition of microorganisms leading the sulfur cycle in the two parent soils. Proteobacteria, Acidobacteria and Chloroflexi were the dominant groups, accounting for 55.19%, 10.61% and 7.18%, respectively. There were significant differences in species classification, and the relative abundance of sulfur-cycling microorganisms in paddy soils developed from granitic parent material was higher. The dominant bacteria in all the channels were the Deltaproteobacteria bacterium, Acidobacteria bacterium, and Betaproteobacteria bacterium, and this abundance accounted for more than 40% of the sulfur-circulating microorganisms in granitic parent paddy soil. However, dominant functional microorganisms involved in each pathway of the sulfur cycle were more abundant in paddy soil developed from Quaternary red clay parent material, for example, Gemmatirosa kalamazoonesis had the highest abundance in organic sulfur transformation pathway while Azoarcus sp. was found in other (transport) pathways. The microorganisms with the highest abundance in the assimilation sulfate reduction pathway are Anaeromyxobacter sp.【Conclusion】The same sulfur cycling pathway was observed in paddy soils derived from red earth with two different parent materials. There was no significant difference in the dominant sulfur-cycling microorganisms in paddy soils derived from red earth with two parent materials at the phylum level. However, there were significant differences in species-level classification, indicating that there is unique dominant sulfur transformation functional flora in soils of different parent materials.
lizhitong, kangzongjing, wangzhihui, zhaoyongpeng, yuzijie, jiangxianjun. The Traits of Microbial Sulfur Cycling Metabolic Pathways in two red paddy soils developed from different Parent Materials[J]. Acta Pedologica Sinica,,[In Press]