DISSERTATION RESEARCH: Systematics and Biogeography of the Genus Hysterangium (Basidiomycota, Phallales)

俄勒冈州立大学的Joseph Spatafora博士和Kentaro Hosaka先生获得了一笔赠款，用于进行“海地菊属的系统学和生物地理学”研究。海宫属是一种能在地下产生子实体的蘑菇状真菌。不像许多地面上的蘑菇，它们可以通过风传播孢子，子宫草的孢子只有在被动物吃掉并与它们的粪便一起沉积时才会传播。这一事实表明，宫腔镜的长距离（如洲际）传播是不可能的。然而，宫缩症的分布是世界性的。这可以用一种假说来解释，即子宫虫是一种相当古老的生物，它现在的分布是由泛大陆的分裂造成的。重要的是，海丝菊与许多不同的树种形成菌根（与根有益的关系）。因为这些关系是特定的，宫子草和寄主树可能共种。本研究的总体目标是通过收集和分析子宫内膜的DNA序列，为子宫内膜的生物地理学和共种性提出强有力的假设。为了实现这一目标，将对以前代表性不足的地区，巴布亚新几内亚、新喀里多尼亚和新西兰进行实地考察，并特别强调南山毛榉森林。海宫草是森林生态系统的重要组成部分。它产生大量的子实体，许多动物在饮食中严重依赖这种地下蘑菇。此外，海丝菊与寄主树的菌根关系是互惠互利的。调查海地属植物群可以更清楚地了解这些生态系统，从而促进更适当的森林管理。尽管真菌是地球上最多样化的生物群体之一，但人们对真菌的生物地理学知之甚少。本研究将为菌根真菌的生物地理和共生模式提供更准确的认识。

A grant has been awarded to Dr. Joseph Spatafora and Mr. Kentaro Hosaka at Oregon State University to conduct the study "Systematics and biogeography of the genus Hysterangium". Hysterangium is a genus of mushroom-forming fungi that produces fruiting bodies below ground. Unlike many of the above ground mushrooms, which can disperse their spores by wind, Hysterangium's spores are only dispersed when consumed by animals and deposited with their feces. This fact implies that long distance (e.g., intercontinental) dispersal of Hysterangium is improbable. The distribution of Hysterangium, however, is worldwide. This can be explained by the hypothesis that Hysterangium is a rather ancient organism and its present distribution was caused by the breakup of the supercontinent Pangaea. Importantly, Hysterangium forms mycorrhizae (beneficial relationships with the roots) with many different tree species. Because these relationships are specific, Hysterangium and host trees may have cospeciated. The overall goal of this study is to develop robust hypotheses for biogeography and cospeciation of Hysterangium by collecting and analyzing DNA sequences. To achieve this goal, field expeditions to previously underrepresented areas, Papua New Guinea, New Caledonia, and New Zealand, will be conducted with a special emphasis on the Nothofagus (southern beech) forests.Hysterangium is an important component of forest ecosystems. It produces abundant fruiting bodies, and many animals are heavily dependent on such below ground mushrooms in their diet. Also, mycorrhizal relationships of Hysterangium and host trees are mutualistic. Surveying the Hysterangium flora of Nothofagus forests provides a more clear understanding of these ecosystems, which in turn facilitates more proper forest management. Despite the fact that fungi are one of the most diverse groups of organisms on earth, biogeography of fungi is poorly understood. This study will provide more accurate understanding of biogeographic and cospeciation patterns of mycorrhizal fungi with Hysterangium as a model organism.