Dissertation Research: Fungal Community Effects on the Seed Bank of a Neotropical Tree

本研究将探讨社区的组成，物种数量，空间结构和生态重要性的真菌感染种子的热带先锋树Cecropia insignis在两个低地森林在巴拿马和哥斯达黎加。本研究将结合联合收割机（i）田间种子死亡率的测定和（ii）分子分析来确定侵染C. insignis种子，和（iii）重新接种健康种子，以确定哪些真菌培养物是致病的。这项研究的结果将提供真菌群落和焦点真菌类群的重要性，在影响人口的一个常见的树种在热带森林中的第一次评估，并将提供第一个详细的特征的真菌群落的身份和多样性与种子的任何树，温带或热带。种子真菌的相互作用进行了一个单一的主机物种在两个最好的研究热带森林的比较将增加重要的新信息，在大空间尺度上的土壤中的真菌的多样性，并提高我们的知识真菌生物多样性的整体。分离株将保存在Gilbertson真菌标本馆（亚利桑那大学），并保存在热带植物相关微真菌的培养物收藏中。新的基因序列数据将提交给在线数据库Genbank。

This research will examine the community composition, number of species, spatial structure and ecological importance of fungi infecting seeds of the tropical pioneer tree Cecropia insignis in two lowland forests in Panama and Costa Rica. This study will combine (i) measurements of seed mortality in the field with (ii) molecular analyses to determine the identities of fungi infecting C. insignis seeds, and (iii) re-inoculation of healthy seeds to determine which fungal cultures are pathogenic. Results of this study will provide the first assessment of the importance of fungal communities and focal fungal taxa in influencing demographics of a common tree species in tropical forests, and will provide the first detailed characterization of the identities and diversity of fungal communities associated with seeds of any tree, temperate or tropical. Comparisons of seed-fungal interactions of a single host species conducted at two of the best-studied tropical forests will add important new information regarding the diversity of fungi in soils at large spatial scales, and enhance our knowledge of fungal biodiversity overall. Isolates will be deposited in the Gilbertson Mycological Herbarium (University of Arizona), and maintained in a culture collection of tropical plant-associated microfungi. Novel genetic sequence data will be submitted to the on-line database Genbank.