GENETIC MAPPING OF QTLs ASSOCIATED WITH GROWTH VIGOUR IN ROSE

Parental linkage maps of a segregating population of diploid rose hybrids (2n=2x =14), composed of 365 uni-parental AFLP and SSR markers, have been constructed using a population (n=88) derived from a cross between two half-sib parents (P119 and P117). Of the markers, 157 P119 markers (85 %) mapped on eight linkage groups and 133 P117 markers (78 %) on seven linkage groups.
The resulting linkage maps of P119 and P117 spanned 463 cM and 491 cM with an average of interval between markers of 2.9 cM and 3.7 cM, respectively.
The present genetic maps were used to identify quantitative trait loci (QTLs) for two growth vigour-related traits, leaf area and chlorophyll content, using the Multiple QTL Mapping approach.
Three QTLs for leaf area and two QTLs for chlorophyll content were identified.
The QTLs accounted, in total, for 50.8 % (range 7.0-23.1 %) and 25.8 % (range 7.6-18.2 %) of the total phenotypic variance for leaf area and chlorophyll content, respectively.
The detection of highly significant major QTLs enables marker-assisted selection for growth vigour in rose.