Jany Jean-Luc, Garbaye Jean, Martin Francis
Unité Mixte de Recherche INRA/UHP 1136 'Interactions arbres/Micro-organismes', Centre INRA de Nancy, 54 280 Champenoux, France.
New Phytol. 2002 Jun;154(3):651-659. doi: 10.1046/j.1469-8137.2002.00408.x.
• The asexual ectomycorrhizal fungus Cenococcum geophilum, known for its wide host and habitat range, has been suggested to provide isolate-dependant drought protection to fine roots. However, little is known about its genetic structure at the fine scale. • Genetic diversity and population structure of C. geophilum at the regional and stand scales was surveyed in five beech (Fagus silvatica) forests in northeastern France. The stands were selected for their contrasting climatic and edaphic features to assess the effect of environmental factors on population structure. • The genetic diversity of C. geophilum was estimated using RAPD, PCR/RFLP of the rDNA internal transcribed spacer (ITS) and PCR/RFLP and sequencing of an anonymous sequence characterized amplified region (SCAR) on ectomycorrhizas and sclerotia-derived mycelial cultures. • A high degree of genetic diversity was observed between and within beech stands in C. geophilum populations. These results suggest the occurrence of a high rate of mitotic or meiotic recombination and an effect of stand features on population structure.
• 土生空团菌这种无性外生菌根真菌，以其广泛的宿主和生境范围而闻名，有人认为它能为细根提供依赖分离物的干旱保护。然而，在精细尺度上对其遗传结构却知之甚少。
• 在法国东北部的五片山毛榉（欧洲水青冈）林中，对土生空团菌在区域和林分尺度上的遗传多样性和种群结构进行了调查。选择这些林分是因其气候和土壤特征具有对比性，以评估环境因素对种群结构的影响。
• 利用随机扩增多态性DNA（RAPD）、核糖体DNA内转录间隔区（ITS）的聚合酶链反应/限制性片段长度多态性（PCR/RFLP）以及外生菌根和菌核衍生的菌丝体培养物上一个特征性扩增区域的匿名序列（SCAR）的PCR/RFLP和测序，来估计土生空团菌的遗传多样性。
• 在山毛榉林分内和林分间的土生空团菌种群中均观察到高度的遗传多样性。这些结果表明存在高频率的有丝分裂或减数分裂重组，以及林分特征对种群结构的影响。
