title: A physical map covering the nsv locus that confers resistance to Melon necrotic spot virus in melon (Cucumis melo L.).
abstract: Melon necrotic spot virus (MNSV) is a member of the genus Carmovirus, which produces severe yield losses in melon and cucumber crops. The nsv gene is the only known natural source of resistance against MNSV in melon, and confers protection against all widespread strains of this virus. nsv has been previously mapped in melon linkage group 11, in a region spanning 5.9 cM, saturated with RAPD and AFLP markers. To identify the nsv gene by positional cloning, we started construction of a high-resolution map for this locus. On the basis of the two mapping populations, F(2) and BC1, which share the same resistant parent PI 161375 (nsv/nsv), and using more than 3,000 offspring, a high-resolution genetic map has been constructed in the region around the nsv locus, spanning 3.2 cM between CAPS markers M 29 and M 132. The availability of two melon BAC libraries allowed for screening and the identification of new markers closer to the resistance gene, by means of BAC-end sequencing and mapping. We constructed a BAC contig in this region and identified the marker 52 K 20 sp 6, which co-segregates with nsv in 408 F(2) and 2.727 BC1 individuals in both mapping populations. We also identified a single 100 kb BAC that physically contains the resistance gene and covers a genetic distance of 0.73 cM between both BAC ends. These are the basis for the isolation of the nsv recessive-resistance gene.
authors.affiliation: Departament de Genètica Vegetal, Laboratori de Genètica Molecular Vegetal CSIC-IRTA, carretera de Cabrils s/n, 08348 Cabrils (Barcelona), Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Morales
authors.forename: Gisella
authors.initials: G
authors.lastname: Orjeda
authors.forename: Cristina
authors.initials: C
authors.lastname: Nieto
authors.forename: Hans
authors.initials: H
authors.lastname: van Leeuwen
authors.forename: Amparo
authors.initials: A
authors.lastname: Monfort
authors.forename: Myriam
authors.initials: M
authors.lastname: Charpentier
authors.forename: Michel
authors.initials: M
authors.lastname: Caboche
authors.forename: Pere
authors.initials: P
authors.lastname: Arús
authors.forename: Pere
authors.initials: P
authors.lastname: Puigdomènech
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Aranda
authors.forename: Catherine
authors.initials: C
authors.lastname: Dogimont
authors.forename: Abdelhafid
authors.initials: A
authors.lastname: Bendahmane
authors.forename: Jordi
authors.initials: J
authors.lastname: Garcia-Mas
mesh_terms: D001483:Base Sequence; D019184:Carmovirus / Q000472:pathogenicity*; D002874:Chromosome Mapping; D022202:Chromosomes, Artificial, Bacterial; D028463:Cucumis melo / Q000235:genetics* / Q000821:virology*; D017931:DNA Primers; D018744:DNA, Plant / Q000235:genetics / Q000302:isolation & purification; D007113:Immunity, Innate; D010935:Plant Diseases / Q000821:virology; D016133:Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D018744:DNA, Plant