Identification of a RAPD Marker Linked to Fusarium Wilt Resistant Gene in Wild Watermelon Germplasm (Citrullus lanatus var. citroides Association Analysis of Fusarium wilt Resistance of Core Collection of Watermelon Germplasms Based on SRAP Markers A New Watermelon Cultivar‘Nongkeda 11’with High Resistance to Fusarium Wilt