Dual Resistance of Melon to Fusarium oxysporum Races 0 and 2 and to Papaya ring-spot virus is Controlled by a Pair of Head-to-Head-Oriented NB-LRR Genes of Unusual Architecture Academic Article uri icon

abstract

  • Dear Editor, Potyviruses such as Papaya ring-spot virus (PRSV) cause important yield losses in cucurbits.Two distinct resistant alleles were identified in the Cucumis melo germplasm.Accession PI 414723 (Supplemental Table 1) possesses monogenic resistance,controlled by the Prv2 allele,and reacts to PRSV by systemic necrotic lesions;plants with the Prv1 allele,described in cultivar WMR-29,remain symptomless (Pitrat and Lecoq,1983).Fusarium oxysporum f.sp.melonis (FUS)exclusively attacks melon,causing severe wilt.Monogenic dominant resistance was described against races 0,1,and 2.The Fom-2 gene,controlling resistance to races 0 and 1,was cloned by Joobeur et al.(2004),and encodes a nucleotide binding domain (NB)-leucine rich repeat (LRR) protein.Our study focused on the Fom-1 gene,which confers resistance to races 0 and 2 (Risser et al.,1976),and on the Prv gene;the two are tightly linked on melon linkage group iX.Molecular markers were developed for the Fom-1/Prv locus,but no study has provided the resolution required for positional cloning.

publication date

  • January 1, 2013