Format: ORAL

Allison MIller1, 2, Zach Harris2,3, Laszlo Kovacs4, Misha Kwasniewski5,Jason Londo6

1 Department of Biology, Saint Louis University, St. Louis, MO, USA 2 Danforth Plant Science Center, St. Louis, MO, USA 3 Taylor Geospatial Institute, St. Louis, MO USA 4 Department of Biology, Missouri State University, Springfield, MO, USA 5 Department of Food Science, Pennsylvania State University, University Park, PA, USA 6 School of Integrative Plant Science, Cornell University, Ithaca, NY, USA

North American grapevines (Vitis spp.) represent a morphologically, genetically, and ecologically diverse group of taxa that are important contributors of regional and global viticulture. Although few North American species are grown directly for grape production, these species have been used for more than one hundred years in the generation of disease-resistant hybrid vines derived from crosses between North American species and the European grapevine (V. vinifera). Beyond their use in hybrid vines, North American Vitis species have also been used as rootstocks: roots of domesticated V. vinifera are susceptible to damage caused by the North American aphid phylloxera, but North American Vitis species can withstand infestation. As a result, North American Vitis species and their hybrid derivatives are widely used as rootstocks for V. vinifera vines on multiple continents. In perennial woody systems like grapevines, a fundamental question is how variation within and among species in below-ground features influences traits expressed in structures above ground, including leaves, flowers, and fruits. In this study, we used a rootstock experimental vineyard in which the clonally propagated grapevine cultivar Chambourcin, a European-American hybrid, was growing ungrafted and grafted to three hybrid rootstocks derived from crosses between V. cinerea ssp. berlandieri, V. riparia, and V. rupestris. Data collected over three years demonstrate seasonal and annual variation in rootstock effects on Chambourcin phenotypes including leaf ion concentrations, gene expression patterns and epigenomic signatures, among others. These data indicate that natural variation grapevine root systems has a detectable influence on a multitude of traits observed in a grafted clonal scion. Additional work is required to document natural variation in wild grapevine species and its genetic and environmental influences, in order to fully leverage these taxa in ongoing efforts to adapt global viticulture for consumer preferences and changing climates.