不同生长年限短萼黄连根内及根际微生物群落多样性研究

Microbial community diversity in roots and rhizosphere soils of Coptis chinensis var.?brevisepala?with different growth years

关键词:  短萼黄连，根际微生物，群落多样性，高通量测序，生长年限

Key words:  Coptis chinensis var.?brevisepala, Rhizospheric microorganism, Community diversity, High-throughput sequencing, Growth years

摘要:

为揭示不同生长年限短萼黄连根组织及根际土壤中的微生物群落的多样性，本研究采用Illumina高通量测序技术对一年生、两年生和多年生短萼黄连的根组织及根际土壤进行测序研究。结果表明：（1）根际土壤微生物群落的α多样性指数（Shannon、Ace、Chao 1）及总操作分类单元（OTUs）数量均显著高于同生长年限的根组织样品。（2）不同年限短萼黄连根组织以变形菌门、放线菌门和子囊菌门为优势菌门，慢生根瘤菌属、根瘤菌属菌群、游动放线菌属和Leptodophora为优势菌属；根际土壤则以变形菌门、放线菌门、子囊菌门和被孢菌门为优势菌门，norank_f_Xanthobacteraceae、慢生根瘤菌属、norank_f_norank_o_Vicinamibacterales、Epicoleosporium和被孢霉属为优势菌属。（3）短萼黄连根内及根际土壤微生物多样性随生长年限变化显著，尤以第一至第二年为关键转变期。（4）LEfSe分析显示，根组织及根际土壤中标志菌群随短萼黄连生长呈现动态变化。一年生根组织显著富集游动放线菌属、假诺卡氏菌属、Epicoleosporium，其根际土壤则显著富集MND1、鞘脂单胞菌属、Epicoleosporium；多年生根组织显著富集慢生根瘤菌属、Steroidobacter、酵母属；其根际土壤则富集慢生根瘤菌属、Candidatus_Xiphinematobacter、木霉属。综上认为，该研究初步阐明了短萼黄连根内及根际微生物群落的结构特征及演替规律，为未来研制促进短萼黄连生长发育及病害防控的微生物制剂提供了重要的理论支撑。

Abstract:

To investigate the characteristics and diversity of microbial communities in roots and rhizosphere soils of Coptis chinensis var.?brevisepala with different growth years, this study employed Illumina high-throughput sequencing technology to sequence the roots and rhizosphere soils of 1-year, 2-year, and perennial plants. The results revealed that: (1) The α diversity indices (Shannon, Ace, Chao 1) and the number of total operational taxonomic units (OTUs) in the rhizosphere soil microbial communities were significantly higher than those in the root tissue samples of the same growth year. (2) Microorganisms in roots were predominantly composed of Proteobacteria, Actinobacteriota, and Ascomycota as the dominant phyla, with Bradyrhizobium, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Actinoplanes, Leptodophora?as predominant genera. In contrast, the rhizospheric soil exhibited?Proteobacteria, Actinobacteriota, Ascomycota, and Mortierellomycota as the primary phyla, while norank_f_Xanthobacteraceae, Bradyrhizobium, norank_f_norank_o_Vicinamibacterales, Epicoleosporium, and Mortierella were identified as the dominant genera. (3) The microbial diversity in both root tissues and rhizosphere soils of?Coptis chinensis?var.?brevisepala?exhibited significant changes with growth years, especially during the critical transition from the first to the second year. (4) Linear discriminant analysis effect size (LEfSe) demonstrated dynamic shifts in signature microbial communities in root tissues and rhizosphere soils across the growth stages of?Coptis chinensis?var.?brevisepala. 1-year-old roots were significantly enriched with Actinoplanes, Pseudonocardia and Epicoleosporium, while their rhizosphere soils were notably enriched with MND1, Sphingomonas and Epicoleosporium. In contrast, Bradyrhizobium, Steroidobacter and Saccharomycopsis were significantly enriched in perennial roots, and Bradyrhizobium, Candidatus_xiphinematter and Trichoderma were preferentially enriched in perennial rhizosphere soils. Through this project, the structural characteristics and succession patterns of microbial communities in roots and rhizosphere soils of Coptis chinensis var. brevisepala were preliminarily elucidated, providing a theoretical foundation for developing microbial agents to enhance growth and disease resistance.