Identification and comparison of indigenous yeast on grapes located within the Lake Erie appelation by sequencing PCR amplified rDNA /

Abstract

Aureobasidium pullulans and Rhodotorula glutinis were identified as the two most common indigenous yeast species identified in the Lake Erie Appellation, using Polymerase Chain Reaction (PCR) and DNA sequence analysis (Beckman CEQ 2000XL) of the ITS (Internal Transcribed Spacer) regions. Field and grape type did not affect variation in distribution of indigenous yeast species present within one vineyard. In addition, field and grape type showed little sequence alignment variation within the same indigenous yeast species. There were, however, outliers identified within the R. glutinis species, but they were not associated with any particular field or grape type. One vineyard from each of the three subdistricts in the Lake Erie Quality Wine Alliance was studied and the dominant species present showed no regional differences in rDNA sequence. Sporobolomyces marcillae was only found in the vineyard located in the Western subdistrict, and was not identified in the eastern and central subdistricts. Year to year variation was seen in indigenous yeast species in that one new isolate was identified (Sporidiobolus pararoseus), but not in rDNA sequence alignment.