小麦/玉米轮作田根际微生物多样性分析

背景] 小麦/玉米轮作是中国粮食作物主要种植模式之一，目前对小麦/玉米轮作田根际土壤微生物差异变化缺乏全面的了解。目的] 明确小麦/玉米根际土壤微生物差异变化并了解其潜在功能。方法] 以小麦/玉米根际土壤为材料，运用细菌16S rRNA基因和真菌rDNA ITS基因测序，分析小麦/玉米根际土壤微生物多样性。结果] 玉米季微生物丰富度高于小麦季，而多样性无明显差异。放线菌门（Actinobacteria）、变形菌门（Proteobacteria）、酸杆菌门（Acidobacteria）和绿弯菌门（Chloroflexi）为小麦季和玉米季根际土壤的优势细菌门，优势真菌门为子囊菌门（Ascomycota）。小麦季和玉米季共有细菌和真菌分别是631个和261个，小麦季特有细菌和真菌分别是38个和58个，玉米季特有细菌和真菌分别是25个和39个。LEfSe分析（LDA阈值为2）细菌和真菌表明，放线菌纲（Actinobacteria）和微囊菌目（Microascales）在小麦季富集，鞘脂单胞菌目（Sphingomonadales）和银耳纲（Tremellomycetes）在玉米季富集。小麦季、玉米季微生物代谢功能不同，与小麦季相比，玉米季养分循环的代谢通路丰富度较高，而参与氧化应激的代谢通路丰富度较低。结论] 该研究结果对指导小麦/玉米轮作田管理具有理论和实践意义。

Diversity analysis of rhizosphere microbial in wheat/maize rotation field

Background] Wheat/maize rotation is one of the main cropping patterns of grain crops in China. At present, there is still a lack of comprehensive understanding of the microbial diversity in rhizosphere soil of wheat/maize rotation field. Objective] The objective of this thesis is to identify the variation of wheat/maize rhizosphere soil microorganisms and understand their potential functions. Methods] In this study, wheat/maize rhizosphere soil was used as material, and bacterial 16S rRNA gene and fungal rDNA ITS gene sequencing were used to analyze the microbial diversity of wheat/maize rhizosphere soil. Results] The results showed that the abundance of microorganisms in maize season was higher than that in wheat season, but there was no significant difference in diversity. Actinobacteria, Proteobacteria, Acidobacteria and Chloroflexi were the dominant phyla of bacterium in the rhizosphere soil in wheat and maize seasons, while Ascomycota was the dominant phylum of fungi. There were 631 and 261 common bacteria and fungus in wheat and maize seasons. There were 38 and 58 unique bacteria and fungus in wheat season, and 25 and 39 unique bacteria and fungus in maize season, respectively. LEfSe analysis (LDA threshold is 2) of bacterium and fungi showed that Actinobacteria and Microascules were enriched in wheat season. Meanwhile, Sphingomonadales and Tremellomycetes were enriched in maize season. Compared with wheat season, the abundance of metabolic pathways involved in nutrient cycling in maize season was higher, while the abundance of metabolic pathways involved in oxidative stress was lower. Conclusion] The results have theoretical and practical significance for guiding the management of wheat/maize rotation fields.