Quantitative trait loci analysis of Plum pox virus resistance in Prunus davidiana P1908: new insights on the organization of genomic resistance regions

Abstract

No valuable source of resistance to Plum pox virus (PPV), the causative agent of sharka disease, has been found in peach (Prunus persica), but polygenic resistance to PPV was described in Prunus davidiana clone P1908. Two previous studies using F 1 and F 2 populations derived from the nectarine cv. Summergrand and P. davidiana P1908 identified a total of six P. davidiana quantitative trait loci (QTLs) involved in PPV resistance (Marcus strain). In an effort to verify the QTL stability in a large progeny and to search for possible interactions of the genetic backgrounds, the current study evaluated the incidence of PPV infection in an F 1 population derived from the susceptible peach cv. Rubira and P. davidiana P1908 over three growth periods using an improved method of PPV phenotyping referred to as "heavy test." The phenotypic dataset was analyzed using similar methods as the previous studies and a newly developed simple-sequence-repeatbased P. davidiana map. Nine regions involved in differential symptom expression were identified among which six were common between studies. However, the level of resistance observed in the population was very low compared to the other studies, and the main QTL previously identified in linkage group 6 was not conserved, suggesting strong interaction of the genetic background of the susceptible parent with that of P. davidiana 1908. Consequently, this could be a limiting factor for developing resistant cultivars derived from P. davidiana P1908.

Generation of Transgenic Rootstock Plum ((Prunus pumila L. × P. salicina Lindl.) × (P. cerasifera Ehrh.)) Using Hairpin-RNA Construct for Resistance to the Plum pox virus

“…Despite numerous efforts to identify the natural Prunus sources of PPV resistance, only a few germplasms are currently known as potential material for breeding [5,6]. In plums, however, natural sources for stable and durable resistance are not available.…”

Evaluation of the Prunus interspecific progenies for resistance to Plum pox virus

“…The heritability of the PPV resistance originating from P. davidiana clone P1908 was further studied by Marandel et al (2009) in the F 2 population derived from the selfing of the individual (#40) of the F 1 population and demonstrated the conservation of four of the six F 1 QTLs. A total of nine Prunus davidiana QTLs involved in PPV resistance were identified in an F 1 population derived from the susceptible peach cultivar Rubira and P. davidiana clone P1908 (Rubio et al 2010). All the studies included the mapping of candidate genes or candidate genelinked simple sequence repeat (SSR) markers.…”

Co-localisation of host plant resistance QTLs affecting the performance and feeding behaviour of the aphid Myzus persicae in the peach tree

“…Because the linkage groups (G) were mainly composed of random amplified polymorphic DNA (RAPD) markers not useful for comparative mapping, the coverage of the map was improved by adding SSR (simple sequence repeat) loci. SSR analysis and map construction were performed using the same SSR primer pairs and procedures as in Rubio et al (2010). In brief, a set of 278 SSR primer pairs developed from several Prunus species were first screened for polymorphism in both parents.…”

“…Franch, a wild species closely related to peach, QTLs linked to resistance to several diseases have been identified on different genetic linkage maps (Foulongne et al, 2003;Rubio et al, 2010). This species is partially resistant to M. persicae.…”