title: Development of the first consensus genetic map of intermediate wheatgrass (Thinopyrum intermedium) using genotyping-by-sequencing.
abstract: Development of the first consensus genetic map of intermediate wheatgrass gives insight into the genome and tools for molecular breeding. Intermediate wheatgrass (Thinopyrum intermedium) has been identified as a candidate for domestication and improvement as a perennial grain, forage, and biofuel crop and is actively being improved by several breeding programs. To accelerate this process using genomics-assisted breeding, efficient genotyping methods and genetic marker reference maps are needed. We present here the first consensus genetic map for intermediate wheatgrass (IWG), which confirms the species' allohexaploid nature (2n = 6x = 42) and homology to Triticeae genomes. Genotyping-by-sequencing was used to identify markers that fit expected segregation ratios and construct genetic maps for 13 heterogeneous parents of seven full-sib families. These maps were then integrated using a linear programming method to produce a consensus map with 21 linkage groups containing 10,029 markers, 3601 of which were present in at least two populations. Each of the 21 linkage groups contained between 237 and 683 markers, cumulatively covering 5061 cM (2891 cM--Kosambi) with an average distance of 0.5 cM between each pair of markers. Through mapping the sequence tags to the diploid (2n = 2x = 14) barley reference genome, we observed high colinearity and synteny between these genomes, with three homoeologous IWG chromosomes corresponding to each of the seven barley chromosomes, and mapped translocations that are known in the Triticeae. The consensus map is a valuable tool for wheat breeders to map important disease-resistance genes within intermediate wheatgrass. These genomic tools can help lead to rapid improvement of IWG and development of high-yielding cultivars of this perennial grain that would facilitate the sustainable intensification of agricultural systems.
authors.affiliation: Department of Plant Pathology, Kansas State University, 4024 Throckmorton, Manhattan, KS, 66506, USA.
authors.forename: Traci
authors.initials: T
authors.lastname: Kantarski
authors.affiliation: USDA-ARS, Forage and Range Research, Utah State University, Logan, UT, 84322, USA.
authors.forename: Steve
authors.initials: S
authors.lastname: Larson
authors.affiliation: Department of Agronomy and Plant Genetics, University of Minnesota, 1991 Buford Circle, St. Paul, MN, 55108, USA.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: The Land Institute, 2440 E. Water Well Rd, Salina, KS, 67401, USA.
authors.forename: Lee
authors.initials: L
authors.lastname: DeHaan
authors.affiliation: Research School of Biology, Australian National University, Canberra, Australia.
authors.forename: Justin
authors.initials: J
authors.lastname: Borevitz
authors.affiliation: Department of Agronomy and Plant Genetics, University of Minnesota, 1991 Buford Circle, St. Paul, MN, 55108, USA.
authors.forename: James
authors.initials: J
authors.lastname: Anderson
authors.affiliation: Department of Plant Pathology, Kansas State University, 4024 Throckmorton, Manhattan, KS, 66506, USA. jpoland@ksu.edu.
authors.forename: Jesse
authors.identifier: http://orcid.org/0000-0002-7856-1399
authors.initials: J
authors.lastname: Poland
mesh_terms: D031702:Agropyron / Q000235:genetics*; D002874:Chromosome Mapping; D015723:Gene Library; D008040:Genetic Linkage; D005819:Genetic Markers; D018745:Genome, Plant; D005838:Genotype; D060005:Genotyping Techniques; D001467:Hordeum / Q000235:genetics; D000069600:Plant Breeding; D011123:Polyploidy; D026801:Synteny
chemical_list: D005819:Genetic Markers