Two genetic linkage maps of tetraploid roses

Abstract

A tetraploid F 2 progeny segregating for resistance to black spot, growth habit, and absence of prickles on the stem and petioles was used to construct genetic linkage maps of rose. The F 1 of the progeny, 90-69, was created by crossing a black spot-resistant amphidiploid, 86-7, with a susceptible tetraploid, 82-1134. The F 1 was open-pollinated to obtain 115 seedlings. AFLP and SSR markers were used to eliminate seedlings produced through cross-fertilization. The remaining progeny set of 52 F 2 plants was used to study the inheritance of 675 AFLPs, one isozyme, three morphological and six SSR markers. AFLP markers were developed with three combinations of restriction enzymes, EcoRI/MseI, KpnI/MseI and PstI/MseI. Most of the markers appear to be in simplex or single-dose and segregated 3:1 in the progeny. One linkage map was constructed for each parent using only the single-dose markers. The map of 86-7 consists of 171 markers assigned to 15 linkage groups and covering more than 902 cM of the genome. The map of 82-1134 consists of 167 markers assigned to 14 linkage groups and covering more than 682 cM of the genome. In the AFLP analysis, EcoRI/MseI generated nearly twice as many markers per run than PstI/MseI. Markers developed with three restriction enzyme combinations showed a mixed distribution throughout the maps. A gene controlling the prickles on the petiole was located at the end of linkage group 7 on the map of 86-7. A gene for malate dehydrogenase locus 2 was located in the middle of linkage group 4 on the map of 86-7. These first-generation maps provide initial tools for markerassisted selection and gene introgression for the improvement of modern tetraploid roses.

Linkage mapping in tetraploid willows: segregation of molecular markers and estimation of linkage phases support an allotetraploid structure for Salix alba × Salix fragilis interspecific hybrids

“…During the last few years, a few theoretical, simulation and explorative studies have been performed to estimate linkage in polyploids (Sorrells, 1992;Wu et al, 1992Wu et al, , 2001Yu and Pauls, 1993;Xu et al, 1995;Hackett et al, 1998;Qu and Hancock, 2001). In addition, both RFLP-and PCRbased markers have been exploited to develop linkage maps of tetraploid species such as potato (Jacobs et al, 1995), sugarcane (Grivet et al, 1996), alfalfa (Brouwer and Osborn, 1999), cotton (Brubaker et al, 1999) and rose (Rajapakse et al, 2001). In general, however, the construction of genetic maps of polyploid species has lagged behind that for diploid species because the statistical methods are far more complicated than for diploids, and little is known about the genomic constitution and pairing behaviour of most polyploids.…”

Towards a unified genetic map for diploid roses

“…This map used a R. multiXoraderived population with 88 F 1 plants and has 520 marker loci. The next published map was developed in a tetraploid population of 52 F 2 plants by Rajapakse et al (2001). The third map (HW) was constructed with AFLP markers by using a diploid population of 91 individuals resulting from an interspeciWc cross between R. wichurana and the dihaploid hybrid H190 (Crespel et al 2002).…”

Microsatellite analysis of Rosa damascena Mill. accessions reveals genetic similarity between genotypes used for rose oil production and old Damask rose varieties

“…Several different types of DNA marker have been successfully applied for rose genotyping (Rajapakse et al 1992;Debener et al 1996;Jan et al 1999;Debener et al 2000;Crespel et al 2002;Esselink et al 2004), to study the domestication process (Martin et al 2001), as well as to study genetic relationships among different rose species and varieties (Rajapakse et al 1992;BenMeir and Vainstein 1994;Ballard et al 1995;Millan et al 1996;Debener et al 1996;Martin et al 2001;Baydar et al 2004;Nybom et al 2004). Furthermore, DNA markers have also been used for the development of genetic linkage maps in roses (Debener and Mattiesch 1999;Rajapakse et al 2001). Highly polymorphic microsatellite markers have been developed for R. hybrida (Esselink et al 2003) and R. wichuraiana .…”