Fungal diversity in eastern Canada forests; biogeography and taxonomy of selected mushrooms

本研究计划有两个目标。第一个目标是利用大规模平行焦磷酸测序技术确定和比较安大略省南部四种不同但相邻的森林类型中土壤、凋落物和木屑中真菌的多样性和群落结构。森林类型将包括三个异养（苏格兰松、铁杉和老硬木）和一个非异养（糖枫）林。我们预测，在异养林分中，地下真菌群落将更加相似，而地上真菌群落在木材和凋落物类型（软木与硬木）方面将更加相似。另一个需要验证的假设是，对环境真菌进行大量DNA采样将获得比Hawksworth（1991）从传统真菌采样方法中报告的平均6:1比例高得多的真菌：植物比例。如果这一假设被证明是正确的，那么全球真菌的多样性可能远远高于预测的150万。本研究的第二个目的是评估选定的加拿大东部具有生态和/或经济重要性的大型真菌的生物地理关系，并重新评估它们的分类。这些真菌属于外生菌根属Amanita、Laccaria、cantharelllus和Hydnum，以及sam纲Xerula、Xeromphalina、Pleurotus和Ganoderma。选择这些分类群是因为它们通常在北半球温带森林中发现，但在分类学上仍然存在问题。我们预测，总的来说，加拿大东部的大型真菌与在阿巴拉契山脉南部发现的物种的关系比它们与美国西部和欧洲物种的关系更密切，因此更倾向于冰川后来自更多南方难民的重新殖民的假设。这也将使许多北美东部分类群的欧洲名称的应用无效，因为它们在过去被广泛使用。

This research proposal has two objectives. The first objective is to determine and compare the diversity and community structure of fungi in soil, litter, and wood debris in four different but adjacent forest types in southern Ontario with the use of massive parallel pyrosequencing. Forest types will include three ectotrophic (scots pine, hemlock, and old growth hardwood) and one non-ectotrophic (sugar maple) stands. We predict that below ground fungal communities will be more similar among ectotrophic stands, while above ground fungal communities will be more similar with respect to wood and litter type (softwood vs. hardwood). Another hypothesis to be tested is that massive DNA sampling of environmental fungi will recover a much higher fungal:plant ratio than the average 6:1 ratio reported by Hawksworth (1991) from traditional fungal sampling methods. If this hypothesis proves correct, then fungal diversity worldwide could be much higher than the predicted 1.5 million. The second objective of this study is to assess the biogeographic relationships of selected eastern Canadian macrofungi of ecological and/or economic importance and to reevaluate their taxonomy. These fungi belong to the ectomycorrhizal genera Amanita, Laccaria, Cantharellus, and Hydnum and the saprobes genera Xerula, Xeromphalina, Pleurotus and Ganoderma. These taxa are chosen because they are commonly found in northern hemisphere temperate forests yet are still taxonomically problematic. We predict that eastern Canadian macrofungi will, in general, be more closely related to species found southward in the Appalaches than they are to western America and European species, thus favoring the hypothesis of post-glacial recolonization from more southern refugees. This would also invalidate the application of European names for many eastern North American taxa as they have largely been applied in the past.