A Protocol for Endophyte-­Free Callus Tissue of the Grape <i>Vitis aestivalis</i> “Norton/Cynthiana” (Vitaceae)

Abstract

Vitis aestivalis is used in commercial wine production. Vegetative propagation of V. aestivalis has shown a low success rate. Although plant tissue culture has been a successful method to propagate many species, V. aestivalis has not yet been reliably grown as pure callus culture due to a fungal endophyte that exists within the plant. This study reports a viable protocol for obtaining fungus-free tissue culture callus from V. aestivalis . Explant tissue was chosen from healthy, actively growing plants grown in a growth room and in a vineyard. Tissues were sterilized with a combination of isopropanol, bleach, and chlorine dioxide gas and plated onto media containing chlorothalonil. The results from this study suggest that in order to obtain endophyte-free callus tissue, vine explants are to be taken from plants grown in a growth chamber simulating springtime conditions, sterilized in a combination of alcohol, bleach, and chlorine dioxide, and plated on selection media containing an antifungal agent, such as chlorothalonil. This technique could potentially be used with plants that have associated endophytes or other contamination problems to establish callus tissue for research and/or commercial propagation efforts.