Outcome of Grafting Vegetables for Soil-Borne Disease Resistance

Grafting disease resistant plants with vulnerable eggplant, tomato, and watermelon crops can help fight fungal wilt symptoms and crop loss from Verticillium dahliae wilt.

Grafting onto Verticillium dahliae wilt-resistant varieties of rootstock does not harm yield, fruit size, or fruit quality for tomatoes, eggplant, or watermelon. For eggplants, ‘Beaufort’ tomato hybrid rootstock grafts decreases wilt symptoms. Both ‘Beaufort’ and ‘Maxifort’ tomato hybrids fight wilt symptoms in tomatoes. Watermelon grafted onto ‘Emphasis’ bottle gourd and ‘Strong Tosa’ squash hybrid had significantly less wilt symptoms than non-grafted plants. However both eggplants and watermelon may still be affected by wilt to some degree. All listed rootstock are commercially available. Before transplanting into a field, grafted plants must heal in a greenhouse. Grafted tomato can tolerate lower relative humidity while healing, but watermelon cannot. 

For information on how to graft vegetables, please visit the WSU Extension page listed in the links section.