The systematics of reduced, soil-inhabiting ascomycetes

缺乏有关真菌的系统发育关系和多样性的信息是严重的，特别是在子囊菌门，一组，包括大多数经济上重要的真菌。 子囊菌在许多栖息地中已经被列举和鉴定，但记录其多样性的研究受到分离方法的选择性和鉴定这些真菌的困难的限制。 许多子囊菌不形成有性状态，并根据它们的无性孢子形式（无性型）来定义。 无性型子囊菌通常在解剖学上是简单的，因此难以识别。 在纯培养中不形成孢子阶段的子囊菌不能使用基于显微镜的方法鉴定。 幸运的是，通过PCR（聚合酶链式反应）-扩增靶基因区域和比较所得扩增子的DNA序列，已经在很大程度上解决了准确鉴定变形和非孢子形成子囊菌的问题。 序列数据也是有价值的推断，允许单系群的识别和基于生态和形态学characters.The拟议的研究将集中在结构简单，土壤栖息，纤维素和角蛋白降解的成员的Chaetomiaceae和Onygenales的系统学和多样性评估的假设的基础上，使用基于培养和分子方法。 毛壳科的调查将测试的假设，即形态反映本属内的系统发育关系。 研究土壤栖息Onygenales将确定是否角蛋白降解的成员，这一命令占主导地位的真菌附近的土壤冬眠的红边束带蛇。 记录这个社区将提高我们的角蛋白降解子囊菌的多样性和分布的理解，并可能有助于确定由真菌引起的爬行动物的新的传染病。 这两项研究都将导致新物种的描述和构建新物种，最终将促进在自然群落中发现毛壳科和Onygenales。

Lack of information concerning the phylogenetic relationships and diversity of fungi is acute, particularly within the Ascomycota, a group that includes the majority of economically important fungi. Ascomycetes have been enumerated and identified in many habitats, but studies documenting their diversity are limited by the selective nature of isolation methods and the difficulty of identifying these fungi. Many ascomycetes do not form sexual states and are defined on the basis of their asexual spore forms (anamorphs). Anamorphic ascomycetes are typically simple anatomically and thus challenging to identify. Ascomycetes that form no spore stages in pure culture cannot be identified using microscopy-based methods. Fortunately, the problem of accurately identifying anamorphic and non-sporulating ascomycetes has been solved largely through the PCR (polymerase chain reaction)-amplification of target gene regions and the comparison of DNA sequences of the resulting amplicons. Sequence data are also valuable for inferring phylogenies that permit the recognition of monophyletic groups and the assessment of hypotheses based on ecological and morphological characters.The proposed research will focus on the systematics and diversity of structurally simple, soil-inhabiting, cellulose- and keratin-degrading members of the Chaetomiaceae and Onygenales using culture-based and molecular methods. Investigation of the Chaetomiaceae will test the hypothesis that morphology reflects phylogenetic relationships within this genus. Study of soil-inhabiting Onygenales will determine if keratin-degrading members of this order dominate the mycota of soil near the hibernacula of red-sided garter snakes. Documenting this community will improve our understanding of the diversity and distribution of keratin-degrading ascomycetes and may assist in identifying of emerging infectious diseases of reptiles caused by fungi. Both studies will result in the description of new species and the construction of phylogenies that will ultimately facilitate the discovery of the Chaetomiaceae and Onygenales in natural communities.