Gordon Johnson, Extension Vegetable & Fruit Specialist; email@example.com
Delmarva watermelon growers have challenges from two soil borne pests, Fusarium Wilt, and Southern Root Knot nematodes. Current management practices include long rotations with non-hosts, soil applied fungicides and soil applied nematicides.
There is now another tool that growers can use to manage these pests where both pathogens are present — grafting watermelon plants onto “Carolina Strongback’ rootstock.
Carolina Strongback was bred by USDA-ARS scientists and was tested by Clemson University researchers in South Carolina. It is a cross between several wild watermelon citron lines and was released in 2019. According to the USDA-ARS “Selected for its grafting qualities and seed production, Carolina Strongback material can be used by seed companies, vegetable grafting companies and watermelon growers as a rootstock for growing susceptible watermelon cultivars in soils infested by the watermelon Fusarium wilt pathogen (races 1 and 2) and (southern) root-knot nematodes”.
This rootstock was used in 2020 with grafted seedless watermelons in many locations and performed well. We expect increased availability in the future.