宁夏枸杞深色有隔内生真菌的侵染特征及多样性

Infection characteristics and diversity of dark septate endophytic fungi isolated from Lycium barbarum in Ningxia

摘要:

【背景】枸杞是享誉中外的名贵药材，深色有隔内生真菌(Dark septate endophytes，DSE)是枸杞内生真菌的重要组成部分。【目的】从宁夏枸杞栽培品种和野生品种的根系分离获得DSE菌株，研究枸杞DSE的群落组成、物种多样性及在宿主植物内的侵染定殖情况。【方法】从宁夏枸杞栽培园采集栽培品种宁杞1号、宁杞3号、宁杞5号、宁杞6号、宁杞7号、宁杞8号以及野生品种黄果枸杞和黑果枸杞共8个枸杞品种的根系，分离DSE菌株，运用形态学特征、rDNA-ITS序列分析进行菌株鉴定，采用回接试验方法确定DSE真菌。【结果】DSE在枸杞根系能形成大量“微菌核”典型结构。从8个枸杞品种根系中共分离获得DSE菌株279株，分属于18个属，具有丰富的物种多样性。镰刀菌属(Fusarium)为各品种的共有属和优势属，相对频率最高达85%。Monosporascus、蓝状菌属(Talaromyces)和俄氏孔菌属(Earliella)为枸杞内首次报道的DSE。枸杞不同品种中DSE群落物种多样性指数、均匀度指数和Simpson指数差异显著。【结论】DSE在枸杞栽培品种及野生品种中具有丰富的生物多样性，能够与枸杞根系形成良好的共生关系，增强了枸杞对生态环境的适应性。

Abstract:

[Background] Lycium barbarum is a traditional edible herb, and dark septate endophytes (DSE) is an important component of endophytic fungi in L. barbarum. [Objective] DSE strains were isolated from the roots of cultivated and wild varieties of L. barbarum in Ningxia. In order to analyze the diversity and the community constitution of DSE associated with L. barbarum and understand the colonization and distribution of DSE in L. barbarum. [Methods] The roots of Ningqi-1, Ningqi-3, Ningqi-5, Ningqi-6, Ningqi-7, Ningqi-8, L. barbarum var. auranticarpum and L. ruthenicummurr were collected from Ningxia wolfberry cultivation garden. Strains were identified by morphological characteristic and rDNA-ITS sequence, and DSE of roots from L. barbarum were validated by Koch’s Rule. [Results] DSE live as mircosclerotia in the roots of L. barbarum. In this paper, 279 DSE were isolated from roots of eight kinds of L. barbarum, belonging to 18 genera, which are rich in species diversity. Fusarium were a common and dominant genus in various breeds. The relative frequency was up to 85%. Monosporascus, Talaromyces and Earliella were firstly reported in L. barbarum. There were significant differences in biodiversity index, evenness index and Simpson’s index of DSE community among different varieties of L. barbarum. [Conclusion] DSE of L. barbarum were rich in resources of cultivated and wild varieties of L. barbarum, DSE could form a symbiotic relationship with L. barbarum and enhance the adaptability of wolfberry to the ecological environment.