Resistance to Cucumber mosaic virus (CMV) in melon Near Introgression Lines (NIL) carrying two or three Quantitative Trait Loci (QTL)

Abstract

Trabajo presentado en la III Reunión de la Red Nacional de Virología de Plantas, RENAVIPLANT, celebrada en Murcia entre el 25 y el 27 de mayo de 2022.Cucumber mosaic virus (CMV) can infect more than 1.200 different plant species belonging to Solanaceae and Cucurbitaceae families. Resistance to CMV has been found in several exotic melon accessions, being one of them the Korean accession “Songwhan Charmi” (SC). A doubled haploid line (DHL) collection was previously developed from a cross between SC as resistant parental and the cultivar Piel de Sapo (PS) as a susceptible parental, in order to study the resistance trait. A Quantitative Trait Loci (QTL) analysis revealed a major QTL, cmvqw12.1, located in the linkage group XII. This QTL confers total resistance to subgroup II strain LS. However, for the subgroup I strains M6 and FNY it is necessary but not sufficient. In addition, two more QTLs were described, cmvqw3.1 located in LGIII and cmvqw10.1 in LGX. DHLs containing the three QTLs were resistant to M6, whereas DHLs containing two QTLs, being one of them cmvqw12.1, were susceptible to M6 strain. In the present work we have developed Near Isogenic Lines (NILs) containing either two or three QTL. These are a NIL with cmvqw3.1 and cmvqw12.1, a NIL with cmvqw10.1 and cmvqw12.1 and a NIL with the three QTL. Our aim is to confirm in the NILs the resistance to CMV-M6 observed previously in the DHLs containing two and three QTLs, in order to know whether the results are consistent in these two different genetic backgrounds. From these ILs we are generating mapping populations for both QTLs cmvqw3.1 and cmvqw10.1