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Elymus L. is the largest and most complex genus in the Triticeae tribe of grasses with approximately 150 polyploid perennial species occurring worldwide. We report here the first genetic linkage map for Elymus. Backcross mapping populations were created by crossing caespitose Elymus wawawaiensis (EW) (Snake River wheatgrass) and rhizomatous Elymus lanceolatus (EL) (thickspike wheatgrass) to produce [F.sub.1] interspecific hybrids that were then backcrossed to the same EL male to generate progeny with segregating phenotypes. EW and EL are both allotetraploid species (n = 14) containing the St (Pseudoroegneria) and H (Hordeum) genomes. A total of 387 backcross progeny from four populations were genotyped using 399 AFLP and 116 EST-based SSR and STS markers. The resulting consensus map was 2574 cM in length apportioned among the expected number of 14 linkage groups. EST-based SSR and STS markers with homology to rice genome sequences were used to identify Elymus linkage groups homoeologous to chromosomes 1-7 of wheat. The frequency of Stderived genome markers on each linkage group was used to assign genome designations to all linkage groups, resulting in the identification of the seven St and seven H linkage groups of Elymus. This map also confirms the alloploidy and disomic chromosome pairing and segregation of Elymus and will be useful in identifying QTLs controlling perennial grass traits in this genus. Key words: Elymus, SSR, molecular markers, genetic map, thickspike wheatgrass, Snake River wheatgrass, rhizome, growth habit. Le genre Elymus est le plus grand et le plus complexe au sein de la tribu des Triticees au sein des graminees avec plus de 150 especes perennes polyploides distribuees de par le monde. Les auteurs rapportent la premiere carte genetique chez le genre Elymus. Des populations de cartographie issues de retrocroisements ont ete produites en croisant un elyme dru, Elymus wawawaiensis (EW; ? Snake River wheatgrass ?), avec un elyme rhizomateux, Elymus lanceolatus (EL ; Agropyre des rives, ? thickspike wheatgrass ?) pour produire des hybrides [F.sub.1] interspecifiques qui ont ensuite ete retrocroises au meme parent m?le EL pour generer une descendance en segregation. Les especes parentales EW et EL sont toutes deux allotetraploides (n = 14) combinant les genomes St (Pseudoroegneria)et H (Hordeum). Au total, 387 descendants de 4 populations retrocroisees ont ete genotypes avec 399 marqueurs AFLP et 116 marqueurs SSR et STS derives d'EST. La carte consensus qui a ete produite totalise 2574 cM repartis sur les 14 groupes de liaison attendus. Les marqueurs SSR et STS derives d'EST presentant de l'homologie avec des sequences genomiques du riz ont ete employes pour identifier les groupes de liaison homeologues aux chromosomes 1 -7 du ble. La frequence de marqueurs provenant du genome St sur chaque groupe de liaison a ete employee pour la designation de tous les groupes de liaison, de telle maniere que les sept groupes de liaison des genomes St et H ont ete identifies chez les Elymus. Cette carte confirme egalement l'allopolyploidie ainsi que l'appariement et la segregation disomiques des chromosomes chez les Elymus et elle sera utile pour identifier des QTL controlant de nombreux caracteres lies a la perennite au sein de ce genre. Mots-cles : Elymus, SSR, marqueurs moleculaires, carte genetique, thickspike wheatgrass, Snake River wheatgrass, rhizome, port. [Traduit par la Redaction], Introduction Several important cereal crops, cultivated forages, annual and perennial grass weeds, and ecologically diverse grasses belong to the tribe Triticeae (Poaceae). The genus Elymus L. (Poaceae: Triticeae) is composed [...]

High nitrogen (N) fertilizer costs and increased environmental stewardship have renewed interest in grass–legume pastures. This research compared herbage mass, nutritive value, steer growth performance and economics of binary mixtures of tall fescue (Schendonorus arundinaceus [Schreb.] Dumort, nom. Cons.) (TF) with alfalfa (ALF) (TF + ALF, Medicago sativa L.) and birdsfoot trefoil (BFT) (TF + BFT, Lotus corniculatus L.), to tall fescue with (TF + N) and without N fertilizer (TF–N). Pastures were established in Lewiston, Utah, USA, and rotationally stocked by Angus beef steers for 112 days in 2012 and 2013. Herbage samples were collected prior to each 7‐day stocking period and analyzed for mass and nutritive value. Steers were weighed each 28‐day rotation cycle and cumulative average daily gain (ADG) calculated. Steer performance differed (p =.05) among most treatments with ADG greatest for TF + BFT (0.73 kg/day) and TF + ALF (0.67 kg/day), followed by TF + N (0.61 kg/day) and the least for TF–N (0.40 kg/day). Multivariate analysis indicated that small inherent differences in herbage energy, fiber and digestibility were highly correlated with steer growth. Other variables associated with ADG included legume proportion and herbage mass. Fescue–legume mixtures had 29 to 33% legume proportion, and more (p =.05) favorable energy and fiber concentrations than grass monocultures. Whereas herbage mass was greatest (p =.05) for TF + N (2,956 kg/ha), followed closely by TF + BFT (2,741 kg/ha) and TF + ALF (2,623 kg/ha). Overall, TF + BFT and TF + ALF pastures had less herbage, but better nutritive value and increased steer growth performance compared to TF + N, without the added cost of fertilizer. [ABSTRACT FROM AUTHOR]