棉花长期连作对新疆农田土壤古菌群落演替的影响

Effect of Cotton Continuous Crop on the Successtion of Edaphic Archaea Community Structure in Xinjiang, China

为了解在新疆干旱半干旱土壤环境下,棉花连作对土壤古菌群落结构造成的影响,基于高通量测序法对阿克苏棉区30年连作期间以及玉米轮作一年后土壤古菌群落结构变化规律进行了对比分析。结果表明,当地原生态土壤古菌群落主要由Thaumarchaeota、SM1K20、Euryarchaeota、Aenigmarchaeota、Crenarchaeota和Marine_Hydrothermal_Vent_Group(MHVG)等6个门组成。棉花第一年种植就引起了土壤古菌群落Shannon等多样性指数和可检测到的种数快速提高,虽然各样品特有操作分类单元数(OUT,operational taxonomic units)相差较大,但各样品共有的核心OTU数仍高达232个,占主要部分。在棉花长期连作过程中,从门到属的不同分类水平上,都有部分组成在丰度上持续发生着调整,但改变的幅度逐年趋小,当连作10年后,新的古菌群落结构逐渐形成。玉米轮作一年古菌群落结构多样性指数和组成成分没有大变化,但Sulfolobaceae和GoM-Arch87两个属的丰度成倍增加。分析认为,当地土壤环境中孕育着极为丰富的特殊古菌资源,棉花长期连作导致新的古菌群落结构形成,作物轮作可以快速调整部分土壤古菌组成丰度。研究结果可为当地古菌资源的开发及耕地微生物群落结构的健康发展提供指导。

The effects of continuous cropping on the soil archaea community structure were rarely reported.In order to identify the structural succession of soil archaea community during long-term cotton continuous cropping in Xinjiang area,high-throughput sequencing was used to analyze and compare the composition of the archaea community in soil by years of continuous cotton cropping and crop rotation over 30 years of cultivation.The results showed that the local original ecological soil archaea community was mainly consisted of six phyla including Thaumarchaeota,SM1K2,Euryarchaeot,Aenigmarchaeot,Crenarchaeot and Marine_Hydrothermal_Vent_Group(MHVG).In the first year of cotton cultivation,the diversity indexes such as Shannon etc and the number of detectable OTU(operational taxonomic units)of soil archaea community,were rapidly increased.Although the number of unique OUT of each sample differed greatly,the core OTU number shared by each sample still accounted for the main part,up to 232.In the process of long-term continuous cropping of cotton,the structure of soil archaea community changed greatly in abundance and composition from phylum to genus level,and the range of the variation trend was smaller year by year,while the new structure composition of soil archaea community tended to be stable till 10 years of continuous cropping later.There was no significant change in the diversity indexes and the main composition of new structure composition of soil archaea community after annual maize rotation,but the abundance of the two genera(Sulfolobaceae and GoM-Arch 87)multiplied.It can be concluded that the unique archaea resources are abundant in the local soil environment and the cultivation of cotton and the associated farming management methods is the main reason to the change of the local soil archaea communities.The crop rotation can quickly adjust the composition abundance of some soil archaea.These results can provide guidance for the development of local archaea resources and the maintenance of healthy cropland microbial community structure.