Fontes de resistência em melancia e meloeiro a vírus do gênero Potyvirus

Abstract

Twenty nine melon and 38 watermelon genotypes were evaluated against mechanical inoculations of Papaya ringspot virus (PRSV), Watermelon mosaic  virus (WMV) e Zucchini yellow mosaic virus (ZYMV), all member of genus Potyvirus, family Potyviridae. Sixteen plants of each genotype were inoculated with eachvirus and maintained at greenhouse conditions, and four plants additional non inoculated plants for each viral species were maintained at the same conditions to work as control. All the plants were observed for symptom development and tested by indirect enzyme linked immunosorbent assay (ELISA), using antisera specific for the referred viruses. According to the results, five melon genotypes showed to be resistant to PRSV; two to WMV and five to ZYMV. Five of these melon genotypes showed multiple resistance to PRSV and WMV; four to PRSV and ZYMV; one to WMV and ZYMV; and three showed multiple resistance to all three virus species. On the other hand, among the 38 watermelon genotypes evaluated, five were resistant to PRSV; six to WMV and no one showed resistance to ZYMV. The genetic variability observed in melon and watermelon genotypes confirmed the possibility for producing hybrids or varieties with multiple resistance to the three most important viruses that infect cucurbits in the Northeast.