野生建兰根系共生真菌群落结构及生物学功能

Community structure and biological function of the root symbiotic fungi of wild Cymbidium ensifolium

摘要:

[目的] 为探究建兰Cymbidium ensifolium根系共生真菌群落结构及生物学功能。[方法] 利用高通量测序技术和FunGulid数据库，对来自湖南省（HN）、福建省（FJ）、贵州省（GZ）和云南省（YN）的4个样品的野生建兰根围土壤、根表和根内3个生态位的共生真菌种群结构与功能进行鉴定和预测。[结果] 建兰根系共生真菌分布在12门44纲103目241科432属中，优势门类为担子菌门Basidiomycota（49.51%）、子囊菌门Ascomycota（27.39%）和被孢霉门Mortierellomycota（20.22%），在属水平上，被孢霉属（Mortierella）（11.75%）、Saitozyma（11.45%）和Papiliotrema （7.93%）为优势属。不同建兰样品的真菌营养类型相差较大，但每个样品在根围土壤和根表间的真菌营养类型相似度高，根内菌均以腐生型为绝对优势类型（50.11%–85.98%），其中FJ样品较为特殊，3个生态位均以腐生营养型占绝对优势（85.98%–94.76%）。根围土壤和根表都以病理-腐生-共生混合型真菌为主，除此之外GZ样品的共生营养型，YN样品的腐生型、共生型，HN样品的腐生型也均为各自的优势营养类型。[结论] 建兰根系共生真菌种类多样性丰富，各样品和各生态位点间的共生真菌群落结构均存在极显著差异。建兰根系共生真菌存在的潜在有益真菌包括被孢霉属、红菇属（Russula）、Saitozyma、Papiliotrema、Cladophialophora等。该研究为揭示建兰根部与真菌的共生关系，以及为建兰共生真菌的开发利用提供了理论基础。

Abstract:

[Objective] To explore the community structure and biological function of Cymbidium ensifolium root symbiosis fungi.[Methods] Using high-throughput sequencing and FunGulid database, fungal species diversity and function of wild C. ensifolium rhizosphere soil (Rs), rhizoplane (Rp), and endoplane (Ep) at 4 samples in Hunan (HN), Fujian (FJ), Guizhou (GZ) and Yunnan (YN) Province were identified and predicted. [Results] The root symbiotic fungi of C. ensifolium are distributed in 12 phyla, 44 classes, 103 orders, 241 families and 432 genera. The main dominant phyla are Basidiomycota (49.51%), Ascomycota (27.39%) and Mortierellomycota (20.22%). At the genus level, Mortierella (11.75%), Saitozyma (11.45%) and Papiliotrema (7.93%) are the dominant genera. The nutrient types of symbiosis fungi in different C. ensifolium samples are quite different, but the structure of fungal nutrient types of each sample had a high similarity between the Rs and Rp; and the saprophytes was the absolute dominant type (50.11%-85.98%) in the Ep. However, FJ sample were special because of saprophytic trophic type dominated in the three ecological niches (85.98%-94.76%). The Rs and Rp fungi around the GZ sample were mainly of Pathotroph-Saprotroph-Symbiotroph and Symbiotroph type. The Rs and Rp of YN sample point were dominated by Saprotroph, Pathotroph-Saprotroph-Symbiotroph and Symbiotroph fungi. The Rs and Rp fungi of HN sample were also mainly composed of Saprotroph and Pathotroph-Saprotroph-Symbiotroph type. [Conclusion] The C. ensifolium root symbiosis fungi exhibit high diversity, and the community structure of the symbiosis fungi between each sample and each ecological niche point has extremely significant difference. The potential beneficial fungi of C. ensifolium root symbiotic fungi include Mortierella, Russula, Saitozyma, Papiliotrema, Cladophialophora, etc. This study provides a theoretical basis for revealing the symbiosis of C. ensifolium roots and fungi, as well as for the development and utilization of C. ensifolium symbiosis fungi.