Disease severity evaluation index of melon landraces from Esfahan area infected with Fusarium oxysporum f. sp. melonis race ۱.۲

Melon (Cucumis melo L.) is an important popular high-consumption product in the world. Melon Fusarium wilt (Fusarium oxysporum f.sp. melonis: FOM) is a global destructive disease. In this research, ۸ melon landraces from Esfahan area with Isabelle and Charentais-T as control genotypes resistant and susceptible, respectively, on completely random block design with three replications and five plants in each replication challenged with ۱.۲ race of F. oxysporum by artificial inoculation. Seedlings were inoculated with a suspension of ۱۰۶ spores/ml at the first true leaf stage. The disease severity index (DSI) was assessed on leaves using a rating scale from ۱ to ۵. Based on the results of means comparisons, DSI value for Isabelle genotype and Zarde shotori were as the most resistant genotype. Habib Abad, Lateefeh Gorgab, Garmak, Barg ney, Shahabadi, Firoozan and Tosrokh genotypes were the most susceptible genotypes against Fom۱.۲ even more than the susceptible control cultivar (Charentais -T).