Graft

The rescue of the European wine-grape (Vitis vinifera) industry from the ravages of Phylloxera disease depended on grafting European cultivars onto Phylloxera-resistant rootstocks of native American species: the northern fox grape (Vitis labrusca) and the southern muscadine (V. rotundifolia). Since 1960 another American species, V. champini, has been widely utilized to confer additional resistance to V. vinifera to root-knot nematode worms. This new rootstock also confers salt tolerance, and hence is particularly useful for sultana grapes grown under irrigation.

The practice of grafting onto disease-resistant stocks now extends even to annual plants like tomato. Disease-sensitive cultivars producing high quality fruit, such as Grosse Lisse, are grafted onto wilt and nematode resistant stocks of varieties that would themselves produce fruit deficient in flavor and nutrients.