Recent research shows that the meat from beef animals finished on pasture has greater concentrations of omega‐3 fatty acid (FA) and conjugated linoleic acids (CLA) compared with animals finished on high‐concentrate diets. However, little is known about the FA concentrations in forage that might alter these FA in the meat of pasture‐finished beef. The objective was to determine the FA variation between and within forage species commonly grown in pastures in the Midwest. A secondary objective was to identify phenotypic characteristics that may be associated with individual FA. The forages analyzed included multiple cultivars of orchardgrass (Dactylis glomerata L.), tall fescue [Lolium arundinaceum (Schreb.) S.J. Darbyshire = Schedonorus phoenix (Scop.) Holub], perennial ryegrass (Lolium perenne L.), and alfalfa [Medicago sativa L. ssp. sativa and falcata (L.) Arcang.]. Grasses had higher amounts of α‐linolenic (C18:3) acid compared with alfalfa. Conversely, alfalfa had larger amounts of linoleic acid (C18:2) than did the grasses. Correlations between phenotypic traits and specific FA were found; plant total chlorophyll had the greatest correlation to total FA concentration. Overall, there is not a large amount of within‐species variation that breeders could use to make large changes in FA concentrations.

Few studies have examined N management strategies to accelerate Miscanthus establishment. 27 Our objectives were: (i) determine differences in biomass yield among various M. × giganteus 28 genotypes as influenced by N management during establishment; (ii) quantify the impact of 29 genotype and N management on biomass composition; and (iii) determine how M. × giganteus 30 genotype and N management influence nitrogen use efficiency (NUE). Four M. × giganteus 31 genotypes were planted near Schochoh, KY and Lafayette, IN in 2010. A two-year total N 32 application of 150 kg ha-1 was applied using various combinations of 50, 75, and 100 kg ha-1 y-1. 33 Control N rates included 0 and 150 kg ha-1 each year. Yield, composition, and NUE of the MS 34 and IL clones were similar. Two-year cumulative yields of Nagara were higher than the other 35 genotypes in KY, and the IL clone in IN. There was no response of yield to N on the silt loam 36 soil in KY, whereas high biomass yields were achieved with 50 kg ha-1 y-1 of N on the sandy 37 loam soil in IN. Yields of plots provided high N in Season 1 were similar to unfertilized control 38 plots in Season 2 suggesting little N carryover from Season 1 to 2. Biomass fiber concentrations 39 were not influenced by N-fertilization, but high leaf retention of the Nagara lines reduced 40 biomass cellulose and lignin concentrations. Site-specific genotypic differences in NUE were 41 observed. Annual N applications of 50 kg ha-1 is recommended to enhanced Miscanthus yield 42 during establishment on the coarse-textured soils.

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Nitrogen (N) reserves in vegetative tissues contribute N to regrowth of Miscanthus × giganteus shoots in spring, but our understanding of how N fertilization and plant genotype affect this process is incomplete. Our specific objectives were to: (1) determine how N fertilizer management impacts accumulation of dry matter and N among aboveground and belowground tissues and organs; (2) understand how changes in N management and tissue N concentration influence seasonal fluctuations in concentrations of buffer-soluble proteins and amino acids in putative storage organs including rhizomes and roots; and (3) characterize genotypic variability and genotype × N interactions for N reserve accumulation and use among Miscanthus × giganteus genotypes. Established plots of the IL Clone and Nagara-sib population were fertilized with 0–0, 0–150, 75–75, 150–0, and 150–150 kg N ha-1 where the first numeral denotes the N rate applied in 2011 (Year 1) and the second number denotes the N rate applied in 2012 (Year 2). Rhizomes, roots, stembases, and shoots were sampled at 6-week intervals between March and August and then in November at dormancy. Concentrations of N, soluble protein and amino-N increased in all tissues with fertilizer N application. With the exception of rhizome amino-N, concentrations of these N pools in roots and rhizomes declined as plants resumed growth in spring and increased sharply between August and November as growth slowed. Losses in shoot and stembase N mass between August and November were similar to total N accumulation in roots and rhizomes during this interval. Compared to the unfertilized control, specific N managements enhanced growth of above- and belowground tissues. The IL Clone generally had greater biomass yield of all organs than the Nagara-sib; the exception being shoot biomass in November when extensive leaf senescence reduce yield of the IL Clone. High biomass yields were obtained with 75 kg N ha-1 applied annually rather than semi-annual N applications of 150 kg N-1 ha that depended on N recycling from roots/rhizomes as a supplemental N source.

Temperate grasses belonging to the Festuca-Lolium complex are important throughout the world in pasture and grassland agriculture. Tall fescue (Festuca arundinacea Schreb.) is the predominant species in the United States, covering approximately 15 million ha. Tall fescue has distinctive morphotypes, two of which are Continental (summer active) and Mediterranean (summer semidormant). This is the first report of a linkage map created for Mediterranean tall fescue, while updating the Continental map with additional simple sequence repeat and sequence-tagged site markers. Addition ally, this is the first time that diversity arrays technology (DArT) markers were used in the construction of a tall fescue map. The male parent (Continental), R43-64, map consisted of 594 markers arranged in 22 linkage groups (LGs) and covered a total of 1577 cM. The female parent (Mediterranean), 103-2, map was shorter (1258 cM) and consisted of only 208 markers arranged in 29 LGs. Marker densities for R43-64 and 103-2 were 2.65 and 6.08 cM per marker, respectively. When compared with the other Poaceae species, meadow fescue (F. pratensis Huds.), annual ryegrass (L. multiflorum Lam.), perennial ryegrass (L. perenne L.), Brachypodium distachyon (L.) Beauv., and barley (Hordeum vulgare L.), a total of 171 and 98 orthologous or homologous sequences, identified by DArT analysis, were identified in R43-64 and 103-2, respectively. By using genomic in situ hybridization, we aimed to identify potential progenitors of both morphotypes. However, no clear conclusion on genomic constitution was reached. These maps will aid in the search for quantitative trait loci of various traits as well as help define and distinguish genetic differences between the two morphotypes.T all fescue (Festuca arundinacea Schreb.) is a member of the Poaceae family and is closely related to the ryegrasses (Lolium spp.). It has been proposed that the Festuca subgenus Schedonorus should be merged with the Lolium genus (Darbyshire, 1993). However, it is clear that Lolium and Festuca fall into discrete taxa based on morphological traits as well as genetic differences (Köl-liker et al., 1999;Catalan et al., 2004;Mian et al., 2005;Kopecký et al., 2009a). Tall fescue is a cross-pollinated species possessing high levels of heterozygosity. Nearly all progeny are genetically unique, and substantial amounts of genetic variation occur both within (71%) and between (29%) populations (Cuyeu et al., 2013). Tall fescue, an allohexaploid (2n = 6x = 42), is part of a larger group of related plants that range from diploid (e.g., F. pratensis Huds.; 2n = 2x = 14) to decaploid (F. arundinacea subsp. cirtensis (St. Yves) J. Gamisans and var.