Phylogenetic Systematics and Diversity of the Agaricales Fungi

Duke University, Durham NC

Investigators

Abstract

f0076023 Vilgalys The study of organismal phylogeny provides a basis for taxonomic classification and also a way to measure the earth's tremendous biological diversity. This project by Prof. Rytas Vilgalys at Duke University and colleagues Dr. Jean-Marc Moncalvo and Dr. James Johnson at Cameron University focuses on phylogenetic systematics of gilled and fleshy mushrooms, in the order Agaricales, and the analysis of biological diversity in this group based on molecular phylogenetic trees. Mushrooms and related fungi are estimated to include over 10,000 species and they are often essential components of terrestrial ecosystems, playing important roles as primary decomposers of organic matter, as mutualistic symbionts of plants, but also as agents of plant and animal disease. The unique biochemical pathways of fungi also represent a largely untapped source of novel metabolites and potential drugs. The project extends current research to incorporate additional sequenced genes from both nuclear and mitochondrial genomes, as evidence to infer phylogenetic relatedness among fungal taxa and to reclassify these fungi into an estimated 25-35 families. This molecular phylogenetic framework in turn permits evaluation of morphological features associated with reduced and enclosed ("puffballs") forms of agaric fungi and also the mycorrhizal habit, to understand the apparently multiple and independent cases of convergent evolution in spore-producing and root-infecting structures. The project will develop a comprehensive DNA sequence database for quick identification and accurate classification of agaric fungi. The study will also develop a theoretical framework for measuring biodiversity based on DNA evidence, which may prove useful for comparative studies and for making conservation decisions based on measures of genetic diversity within geographic areas.