The primary task of a rootstock in viticulture is protection against phylloxera, for which hybrids based on the American species Vitis riparia, Vitis rupestris, and Vitis berlandieri are used. Unlike fruit crops, the rootstock here is not intended to create dwarfing forms but acts as an environment-adaptive element that determines graft take, mineral nutrition, and resistance to unfavorable soil factors such as excess lime, salinity, or nematodes.
A key parameter is the anatomical compatibility, or affinity, between the scion and the rootstock, which determines the efficiency of nutrient transport. When selecting a rootstock, agronomists evaluate its influence on the vine's vigor, which allows for the regulation of the balance between vegetative mass and crop quality, depending on water availability and soil type.
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Rootstock.