Detection of quantitative trait loci for leaf rust resistance in wheat––T. timopheevii/T. tauschii introgression lines

Abstract

Advanced backcross QTL analysis was used to identify QTLs for seedling and adult plant resistance to leaf rust in introgression lines derived from a cross between the spring wheat cultivar 'Saratovskaya 29' and a synthetic allopolyploid wheat (T. timopheevii/T. tauschii). F 2 mapping populations involving two backcross selections ('BC5' and 'BC9' lines) were genotyped with microsatellite markers. Two significant QTL for adult plant resistance were identified in line 'BC5': one on chromosome 2B, but originating from chromosome 2G, explained 31% of the trait variance. The other, derived from T. tauschii and mapped to the short arm of chromosome 2D explained 19% of the trait variance. In the second line, one major seedling and adult plant resistance QTL was identified on chromosome 2B. Both QTL co-located to the same marker interval. Such introgression lines, resulting from the reconstruction of common wheat genome, are of interest both as initial material for breeding and improvement of current cultivars, and as a resource for the study of the interaction and transformation of genomes.

Mapping of quantitative adult plant field resistance to leaf rust and stripe rust in two European winter wheat populations reveals co-location of three QTL conferring resistance to both rust pathogens

“…Whether or not Lr13 had a modulating effect on the leaf rust resistance QTL detected in this study remains unknown. Several QTL studies (Messmer et al 2000; Xu et al 2005a, b; Leonova et al 2007; Rosewarne et al 2008; Prins et al 2011) detected QTL of various leaf rust related traits at a similar location. This repeated finding highlights the importance of the centromeric region of 2BS for leaf rust resistance.…”

Molecular cytogenetic characterization and SSR marker analysis of a leaf rust resistant wheat line carrying a 6G(6B) substitution from Triticum timopheevii (Zhuk.)

“…In populations that carry 6G.6B chromosome translocations, all ten SSR markers tested can be used to detect the presence of breakpoints between the 6G segments and 6B chromosomes. Leonova et al (2002Leonova et al ( , 2007Leonova et al ( , 2008Leonova et al ( , 2010 and Gordeeva et al (2009) used wheat SSR markers to estimate polymorphism between T. timopheevii and wheat parental lines and to identify introgressed T. timopheevii chromosome segments in wheat derivatives; 70-90% of markers showed polymorphisms, with the highest percentage for A genome markers. In the present study microsatellite primer Xgwm626 did not amplify any fragments in T. timopheevii as also reported by Leonova et al (2002).…”

“…The number of transferable wheat EST-SSR markers in the T. timopheevii genome is significantly higher than that of SSR markers (Dobrovolskaya et al 2009). Wheat SSR markers (Xgwm, Xgdm) were used for mapping resistance genes and for detecting introgressions from T. timopheevii into common wheat genotypes (Järve et al 2000;Leonova et al 2002Leonova et al , 2004Leonova et al , 2007Leonova et al , 2008Leonova et al , 2010Brown-Guedira et al 2003;Perugini et al 2008;Gordeeva et al 2009;Maxwell et al 2009). Dobrovolskaya et al (2009) used wheat SSR and EST-SSR markers in the construction of genetic maps of the A t genome of T. timopheevii and to study synteny between the A t and A (wheat) genomes.…”

Selecting a set of wild barley introgression lines and verification of QTL effects for resistance to powdery mildew and leaf rust

“…Not only quantitative traits were dissected by ILs, but also qualitative traits, which are affected by a single or a few loci. Examples for investigation of disease resistances are described for wheat (Leonova et al 2007;Simón et al 2007;Song et al 2007), but also for tomato (Finkers et al 2007). The above-mentioned barley S42 pre-ILs were evaluated with regard to disease resistances, agronomic performance, and malting quality (von Korff et al 2005(von Korff et al , 2006(von Korff et al , 2008.…”