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Key message: Three independent experiments with different genetic backgrounds mapped the resistance gene Pm7 in the oat genome to the distal part of the long arm of chromosome 5D. Resistance of oat to Blumeria graminis DC. f. sp. avenae is an important breeding goal in Central and Western Europe. In this study, the position of the effective and widely used resistance gene Pm7 in the oat genome was determined based on three independent experiments with different genetic backgrounds: genome-wide association mapping in a diverse set of inbred oat lines and binary phenotype mapping in two bi-parental populations. Powdery mildew resistance was assessed in the field as well as by detached leaf tests in the laboratory. Genotyping-by-sequencing was conducted to establish comprehensive genetic fingerprints for subsequent genetic mapping experiments. All three mapping approaches located the gene to the distal part of the long arm of chromosome 5D in the hexaploid oat genome sequences of OT3098 and ‘Sang.’ Markers from this region were homologous to a region of chromosome 2Ce of the C-genome species, Avena eriantha, the donor of Pm7, which appears to be the ancestral source of a translocated region on the hexaploid chromosome 5D. [ABSTRACT FROM AUTHOR]

Key message : Genetic diversity in elite rye germplasm as well as F testcross design enables fast QTL mapping to approach genes controlling grain yield, grain weight, tiller number and heading date in rye hybrids. Abstract: Winter rye ( Secale cereale L.) is a multipurpose cereal crop closely related to wheat, which offers the opportunity for a sustainable production of food and feed and which continues to emerge as a renewable energy source for the production of bioethanol and biomethane. Rye contributes to increase agricultural crop species diversity particularly in Central and Eastern Europe. In contrast to other small grain cereals, knowledge on the genetic architecture of complex inherited, agronomic important traits is yet limited for the outbreeding rye. We have performed a QTL analysis based on a F design and testcross performance of 258 experimental hybrids in multi-environmental field trials. A genetic linkage map covering 964.9 cM based on SSR, conserved-orthologous set (COS), and mixed-phase dominant DArT markers allowed to describe 22 QTL with significant effects for grain yield, heading date, tiller number, and thousand grain weight across seven environments. Using rye COS markers, orthologous segments for these traits have been identified in the rice genome, which carry cloned and functionally characterized rice genes. The initial genome scan described here together with the existing knowledge on candidate genes provides the basis for subsequent analyses of the genetic and molecular mechanisms underlying agronomic important traits in rye. [ABSTRACT FROM AUTHOR]

Key message: A comparative genetics approach allowed to precisely determine the map position of the restorer gene Rfp3 in rye and revealed that Rfp3 and the restorer gene Rfm1 in barley reside at different positions in a syntenic 4RL/6HS segment. Abstract: Cytoplasmic male sterility (CMS) is a reliable and striking genetic mechanism for hybrid seed production. Breeding of CMS-based hybrids in cereals requires the use of effective restorer genes as an indispensable pre-requisite. We report on the fine mapping of a restorer gene for the Pampa cytoplasm in winter rye that has been tapped from the Iranian primitive rye population Altevogt 14160. For this purpose, we have mapped 41 gene-derived markers to a 38.8 cM segment in the distal part of the long arm of chromosome 4R, which carries the restorer gene. Male fertility restoration was comprehensively analyzed in progenies of crosses between a male-sterile tester genotype and 21 recombinant as well as six non-recombinant BCS lines. This approach allowed us to validate the position of this restorer gene, which we have designated Rfp3, on chromosome 4RL. Rfp3 was mapped within a 2.5 cM interval and cosegregated with the EST-derived marker c28385. The gene-derived conserved ortholog set (COS) markers enabled us to investigate the orthology of restorer genes originating from different genetic resources of rye as well as barley. The observed localization of Rfp3 and Rfm1 in a syntenic 4RL/6HS segment asks for further efforts towards cloning of both restorer genes as an option to study the mechanisms of male sterility and fertility restoration in cereals. [ABSTRACT FROM AUTHOR]

Key message: The rye-derived dwarfing gene Ddw1 on chromosome 5R acts in triticale in considerably reducing plant height, increasing FHB severity and delaying heading stage. Abstract: Triticale, an amphiploid hybrid between durum wheat and rye, is an European cereal mainly grown in Germany, France, Poland, and Belarus for feeding purposes. Dwarfing genes might further improve the genetic potential of triticale concerning lodging resistance and yield. However, they might have pleiotropic effects on other, agronomically important traits including Fusarium head blight. Therefore, we analyzed a population of 199 doubled haploid (DH) lines of the cross HeTi117-06 × Pigmej for plant height, heading stage, and FHB severity across 2 locations and 2 years. The most prominent QTL was detected on chromosome 5R explaining 48, 77, and 71 % of genotypic variation for FHB severity, plant height, and heading stage, respectively. The frequency of recovery in cross validation was ≥90 % for all three traits. Because the markers that detect dwarfing gene Ddw1 in rye are also in our population the most closely linked markers, we assume that this major QTL resembles Ddw1. For FHB severity two, for plant height three, and for heading stage five additional QTL were detected. Caused by the considerable genetic variation for heading stage and FHB severity within the progeny with the dwarfing allele, short-strawed, early heading and FHB-resistant lines can be developed when population size is large enough. [ABSTRACT FROM AUTHOR]