摘要：

为了探讨蚯蚓粪是否能对设施内外玉米土壤细菌多样性产生影响,以便在微生物水平上研究蚯蚓粪对设施内外土壤生态质量差异提供参考。基于Illumina NovaSeq测序平台,对不同种植模式(分别为蚯蚓粪设施内外和常规设施内外种植模式下不同品种玉米)下的玉米的根际土壤细菌进行 16Sr RNA 测序。质控后共获得 35 627个操作分类单元(Operational taxonomic units,OTUs),共计 1 832 428 条有效序列。比较不同种植模式下土壤样本OTU数、细菌群落结构组成、相对丰度、优势菌属组间差异性及细菌多样性分析的差异性。土壤样本OTU数在蚯蚓粪和常规种植模式下差异明显,蚯蚓粪种植OTU数高于常规种植,而与设施内外和不同玉米品种间差异不明显;土壤群落结构的优势菌门基本相同,但是在设施内外与是否施用蚯蚓粪之间的细菌门所占丰度大小之间存在较大差异,而在不同玉米品种之间的差异不大。在门水平上,变形菌门和细菌门在常规种植设施内外玉米(D类)中相对丰度比在蚯蚓粪种植的设施内外玉米(E类)高,而放线菌门和芽单胞菌门在蚯蚓粪种植的设施内外玉米(E类)比在常规的设施内外玉米(D类)中相对丰度高。在属水平上,鞘氨醇单胞菌属、Unclassified_Gemmatimonadaceae、Subgroup_10、Uunclassified_Bacteria和Unclassified_Vicinamibacteraceae,这5个属在蚯蚓粪种植中丰度高于常规种植,而Unclassified_Microscillaceae、交替赤杆菌属、黄杆菌属,Unclassified_Vicinamibacteraceae和Uncultured_gamma_proteobacterium,这5个属在常规种植中丰度高于蚯蚓粪种植。多样性分析结果显示,蚯蚓粪种植(E类)的Chao1、Ace和Shannon、Simpson指数显著高于常规种植(D类)。蚯蚓粪种植模式的土壤细菌数量和多样性高于常规模式种植,不同种植模式显著影响土壤细菌群落构成。

关键词: 设施种植, 土壤细菌, 群落结构, 多样性, 高通量测序

Abstract:

To investigate whether earthworm castings can affect the bacterial diversity of maize soil inside and outside the facility,so as to provide a reference for studying the difference in soil ecological quality between earthworm castings inside and outside the facility at the microbial level.Based on Illumina NovaSeq sequencing platform,16S rRNA sequencing was performed on rhizosphere soil bacteria of maize in different planting modes(different varieties of maize in and outside earthworm manure facilities and different varieties of maize in and outside conventional facilities).A total of 35 627 operational taxonomic units(OTUs)were obtained after quality control,with a total of 1 832 428 valid sequences.The OTU number of soil samples,bacterial community structure,relative abundance,the difference between dominant bacteria genera and groups,and the difference in bacterial diversity analysis were compared under different planting patterns.The OTU number of soil samples was significantly different between earthworm droppings and conventional planting mode.The OTU number of earthworm droppings was higher than that of conventional planting,but the difference was not significant between earthworm droppings and different maize varieties.The dominant microphyla of soil community structure were basically the same,but there was a large difference in the abundance of microphyla between inside and outside the facility and whether or not earthworm castings were applied,and there was little difference between different maize varieties.At the phylum level,the relative abundance of Proteobacteria and Bacteria in and outside conventional planting facilities(class D)was higher than that in and outside vermicomical planting facilities(class E),while the relative abundance of Actinobacteria and Blastomonas in and outside conventional planting facilities(class E)was higher than that in and outside conventional planting facilities(class D).At the generic level,Sphingomonas,Unclassified_Gemmatimonadaceae,Subgroup_10,Unclassified_Bacteria and Unclassified_Vicinamibacteraceae were found to be more abundant in worm castings than in conventional ones.While Unclassified_Microscillaceae,Altererythrobacter,Flavobacterium,Unclassified_Vicinamibacteraceae and Uncultured_gamma_proteobacterium,these five genus had a higher abundance in conventional cultivation than in vermicompost cultivation.The results of diversity analysis showed that the Chao1,Ace,Shannon and Simpson indices of earthworm manure planting(type E)were significantly higher than those of conventional planting(type D).The number and diversity of soil bacteria in earthworm manure planting mode were higher than those in conventional planting mode,and different planting modes significantly affected the composition of soil bacterial community.

Key words: Facility cultivation, Soil bacteria, Community structure, Diversity, High-throughput sequencing