RESISTANCE OF CUCURBITA SPP. TO FUSARIUM SOLANI FOR USE AS ROOTSTOCK

ABSTRACT Fusarium solani f. sp. cucurbitae (Fsc) is a soil pathogen and the adoption of resistant rootstocks is an effective method of control. Hybrids of Cucurbita spp. are the main rootstock used for watermelon. This study aimed to evaluate the virulence of Fsc race 1 (Fsc1) in three cucurbits and check the reaction of Cucurbita spp. genotypes to the fungus for its use as rootstock. Four experiments were performed. The virulence of Fsc1 in melon, watermelon and Cucurbita spp. was evaluated in experiment I. In experiment two and three the severity of the pathogen in 19 cucurbits was analyzed. And experiment four evaluated the compatibility of these genotypes as a rootstock for watermelon. Cucurbita spp. proved to be more resistant to Fusarium solani f. sp. cucurbitae race 1 than the melon. The high frequency of plants resistant to Fsc1 was found in the genotypes BGC622, BGC620, BGC567, BGC530, BGC186, BGC381, BGC692, BGC082, ES0061 and ES0062. In addition, the evaluated genotypes may be used as watermelon rootstocks, except for the ES530 strain, which was incompatible with the cultivar BRS Opara, but could be used in pumpkin breeding programs, as well as other resistant genotypes.