The Agriculture Research Service, U.S. Department of Agriculture, announces the release of ‘RKVL-318’, a novel germplasm line useful as a rootstock and as a genetic resource for enhancing resistance to root-knot nematodes (RKNs) in watermelon cultivars. ‘RKVL-318’ is derived from the wild-type watermelon Citrullus lanatus (Thunb.) Matsum. et Nakai subsp. lanatus var. citroides (Bailey) Mansf. ex Greb. (CLC) that is indigenous to southern Africa. The ‘RKVL-318’ plants are resistant to the southern RKN (Meloidogyne incognita), peanut RKN (Meloidogyne arenaria), and Javanese RKN (Meloidogyne javanica). The watermelon plants grafted on ‘RKVL-318’ rootstock had considerable yield advantage over non-grafted watermelon plants in fields infested with RKN. ‘RKVL-318’ should be useful in breeding programs aiming to develop RKN-resistant rootstocks for grafted watermelon or to enhance RKN resistance in watermelon cultivars. ‘RKVL-318’ was developed at the USDA, ARS, U.S. Vegetable Laboratory, Charleston, SC, by Dr. Judy A. Thies, Research Plant Pathologist, and Dr. Amnon Levi, Research Plant Geneticist.
Thies, J.A., Ariss, J., Hassell, R., Buckner, S. & Levi, A. 2015 Accessions of Citrullus lanatus var. citroides are valuable rootstocks for grafted watermelon in fields infested with root-knot nematodes HortScience 50 4 8
Thies, J.A., Ariss, J.J., Hassell, R.L., Olson, S., Kousik, C.S. & Levi, A. 2010 Grafting for management of southern root-knot nematode, Meloidogyne incognita, in watermelon Plant Dis. 94 1195 1199
Thies, J.A. & Levi, A. 2007 Characterization of watermelon (Citrullus lanatus var. citroides) germplasm for resistance to root-knot nematodes HortScience 42 1530 1533
Yetisir, H., Sari, N. & Yucel, S. 2003 Rootstock resistance to fusarium wilt and effect on watermelon fruit yield and quality Phytoparasitica 3 163 169