RT Journal Article SR Electronic T1 Comparison of Grape Chitinase Activities in Chardonnay and Cabernet Sauvignon with Vitis rotundifolia cv. Fry JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 81 OP 85 DO 10.5344/ajev.2005.56.1.81 VO 56 IS 1 A1 Steven Van Sluyter A1 Michael J. Durako A1 Christopher J. Halkides YR 2005 UL http://www.ajevonline.org/content/56/1/81.abstract AB Fungal resistance in Euvitis is generally correlated with levels of pathogenesis-related proteins such as chitinase. Vitis rotundifolia is resistant to many pathogens that affect Vitis vinifera; therefore, grape chitinase activities were compared in V. rotundifolia cv. Fry and V. vinifera cvs. Cabernet Sauvignon and Chardonnay. Cabernet Sauvignon and Chardonnay chitinase activities were approximately 130-fold and 80-fold higher than Fry activities, respectively. Thus, the high pathogen resistance of Fry may be a result of factors other than chitinase. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fry berries had two chitinase isoforms, and at least one was not found in the V. vinifera berries. Cabernet Sauvignon and Chardonnay had four and five chitinase isoforms, respectively.