棉秸秆自然腐解过程中细菌菌群多样性分析

【目的】 分析棉秸秆在自然腐解过程中细菌群落组成和多样性,获得与棉秸秆腐解有关的优势细菌菌属,为秸秆腐熟菌剂的制备奠定基础。【方法】 采用高通量测序技术,对棉秸秆自然腐解过程、不同时间样品中的细菌16S rDNA基因的V4区测序,利用生物信息学方法分析测序结果。【结果】 测序共得到354 067条有效序列,2 111条OTU序列,腐解初期有268个菌属,中期有300个菌属,末期有325个菌属。菌群α多样性指数分析显示,随着腐解时间的延长,7 d以后菌群多样性增加,与起始时相比差异显著(P＜0.05),而7~28 d菌群多样性差异不显著(P＞0.05)。在整个堆制过程中始终存在的优势菌属包括鞘氨醇杆菌属(Sphingobacterium)、橄榄球菌属(Olivibacter)、假黄单胞菌属(Pseudoxanthomonas)、德沃斯氏菌属(Devosia)、根瘤菌属(Rhizobium)。【结论】 棉秸秆自然腐解过程中,在7 d时细菌群落多样性在属水平上与腐解起始阶段差异显著(P＜0.05),随着腐解时间延长,菌落多样性趋于一致;在整个腐熟过程中始终存在五个优势属,功能预测为降解纤维素、木质素、果胶类物质以及提供氮素营养。

Analysis on the Diversity of Bacterial Flora during the Natural Decomposing Process of Corn Straws by Illumina Miseq Sequencing

【Objective】 This project aims to analyze the composition and diversity of bacterial flora in the process of natural decomposition of cotton straw and obtain the dominant bacterial genera related to its decomposition, thus laying a foundation for the preparation of maturing fungicides.【Methods】 High-through sequencing was used to sequence the V4 region in 16S rDNA and based on this, the sequencing result was analyzed by bioinformatics methods.【Results】 There were 354,067 effective tags, 2,111 OTUs, 268 bacterial genus at the beginning of degradation, 300 bacterial genera at the middle of degradation, 325 genera at the end. It was shown by α diversity index that the diversity of bacterial community was increased after 7days. The difference was significant compared with that at the beginning(P＜0.05). The diversity difference was not significant during 7 to 28 days(P＞0.05). The dominant bacterial genera that existed during all the degradation included Sphingobacterium,Olivibacter,Pseudoxanthomonas,Devosia and Rhizobium. 【Conclusion】 During the natural decomposition of cotton straw, the diversity of bacterial community at the genus level was significantly different from that at the initial stage of decomposition at the 7th days(P＜0.05). With the prolongation of decomposing time, the diversity of colony tended to converge. There were five genus that existed as dominant genera throughout the decaying process. The function of these genera were predicted as degrading substance such as cellulose,lignin,pectic substance, which provided the nitrogen nutrition.