Master of Science in Biological Sciences, Youngstown State University, 2008, Department of Biological Sciences and Chemistry

A genetic analysis of samples of Juglans nigra (Black Walnut) from three different locations in Zoar Valley, New York, was conducted. Nuclear ribosomal DNA (nrDNA) intragenic spacer regions (ITS1, ITS2) were PCR amplified along with the 5.8S ribosomal RNA (rRNA) gene. Consensus sequence alignment of J. nigra DNA samples from Zoar Valley showed sequence variation (both base additions and substitutions)between samples. It is likely that at least some of the base substitutions in the consensus sequence are not an artifact of the method, and are different from the published sequence for J. nigra. This indicates the method has potential for examining within species variation for different populations of J. nigra.A survey of fungi associated with the phyllosphere of two elm species native to Zoar Valley, NY, Ulmus americana and Ulmus rubra, was conducted on samples recovered from Zoar Valley, NY. Fungi were identified by sequencing cloned DNA of PCR amplified ribosomal DNA (rDNA) extracted from leaf tissue. Probable endophytes were identified (Phoma, Coprinellus), but the majority of fungi detected (Cryptococcus, Ampelomyces, Colletotrichum) were most likely parasites. Multiple genera of fungi were detected in single leaf tissue samples.

Committee: Carl Johnston PhD (Advisor); Thomas Diggins PhD (Committee Member); Heather Lorimer PhD (Committee Member) Subjects: Molecular Biology