Identification of common genomic regions controlling resistance to Mycosphaerella pinodes, earliness and architectural traits in different pea genetic backgrounds

In a previous study a genetic map had been developed using a RIL population derived from a cross between the Pisum sativum ssp. syriacum accession P665 and the P. sativum ssp. sativum cv. Messire. This population segregated for several agricultural important traits and was successfully used to identify QTLs (Quantitative Trait Loci) controlling resistance to Mycosphaerella pinodes and Orobanche crenata, earliness, root length and aerial biomass. However, this map contained only a few markers in common with the international pea consensus map, hampering comparison with other pea maps. The objective of this study was to incorporate a set of common transferable and reproducible markers into the P665 x Messire map to favour comparative mapping and QTL validation. Seventy-eight out of the 248 SSRs assayed resulted polymorphic in the parental lines. Thirty-eight of them, uniformly distributed all over the genome, were genotyped in the whole population and included in the map. This SSR enriched map allowed identification of six new QTLs (three for resistance to M. pinodes, two for resistance to broomrape and one for root length). Inclusion of the SSRs confirmed the homology of some of the QTLs identified in the population P665 x Messire with other QTLs associated with related traits in different pea genetic backgrounds.