Identification of Fusarium wilt resistance sources in melon (Cucumis melo L.) landraces of Iran using marker-assisted selection technique

Abstract

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, 88 melon landraces from different geographical regions of Iran together with reference genotypes as control genotypes were screened for resistance to 0 and 1 races of Fusarium wilt disease agent using artificial inoculation and two functional markers for the presence or absence of Fom-2 gene. The landraces in multiple replicates were examined in a greenhouse experiment. Thirty-five out of the 88 landraces were selected to determine the disease incidence percentage (DIP), disease severity percentage (DSP) and area under disease progress curve (AUDPC). Based on the results of marker-assisted selection, 83 genotypes had at least one susceptible allele, while 43 heterozygote genotypes had at least one resistance allele. Among genotypes evaluated in artificial inoculation test, three landraces including Shahd-e-Shiraz Gosht Narenji, Korki and Alam Gorgor indicated the highest level of resistance. It seems that these landraces can be considered as the most useful sources of resistance in breeding programs for introducing Fusarium resistant melons. In contrast, Jalali, Petra falat and Habib-Abad landraces were the most sensitive genotypes, which can be used to produce sensitive standard check lines.