The malting barley (Hordeum vulgare L.) industry is often challenged by the availability of sufficient volume and quality to meet demand. Our objective was to evaluate the effects of agronomic practices on grain uniformity, protein concentration, yield, and yield components. Field experiments were conducted from 2005 to 2008 at eight rain‐fed locations in western Canada. The effects of two seeding rates (200 and 400 seeds m−2) and five N (0, 30, 60, 90, and 120 kg ha−1) rates on two two‐row barley cultivars (‘AC Metcalfe’ and ‘CDC Copeland’) were determined. Each experiment was conducted for 3 yr at each location (24 environments). CDC Copeland displayed some advantages over AC Metcalfe including higher grain yield, lower protein and more uniform kernels. For both cultivars, kernel weight, and plumpness were lower at the higher seeding rate; protein was also lower, maturity was earlier and kernels were more uniform. With increasing N rate, barley yield, kernel weight, and tillers plant−1 increased, but days to seed maturity and protein concentration also increased, and kernel plumpness and seed uniformity decreased. The increase in protein was less pronounced with CDC Copeland suggesting that there may be less risk with this cultivar of unacceptable protein levels at relatively high N rates. At many environments barley plant stand decreased while lodging increased with increasing N rates. To improve the likelihood that barley will be acceptable for malting growers should select low‐protein varieties, seed at relatively high rates and limit N application.

that sufficient compaction occurs for exclusion of O 2 , that the fermentation processes of ensiling occur, and Cereals are an important substrate for silage production in the that overheating does not occur. However, moisture short growing season of the northern Prairies. Our objectives were to determine the effects of seeding rate, species, and harvest date contents Ͼ700 g kg Ϫ1 can lead to seepage problems from on the forage yield and quality of cereals. Three field studies were the silo or pit, nutrient loss due to leakage, dilution of conducted to evaluate the productivity of barley (Hordeum vulgare acid levels, and poor preservation of the silage. Ensiling L.), oat (Avena sativa L.), triticale (ϫ Triticosecale rimpaui Wittm.), does not increase the quality of the feedstuffs, so it is and rye (Secale cereale L.) grown as monocrops or in various mixtures.important that high-quality material is put into the silo. Seeding rates ranged from 250 to 750 seeds m Ϫ2 . Harvest times wereThe value of high-quality forage for high production based on the maturity of the principal cereal in each mixture. Few rates from ruminant animals was discussed by Waldo effects of seeding rate on yield or quality were found, but when effects and Jorgensen (1981) and Linn and Martin (1989). Highwere found, higher seeding rates were associated with higher yields, quality forage must have high intake, digestibility, and lower moisture content, and higher fiber content. All treatments proefficiency of utilization. Cell walls are an important comduced high quality forage as measured by neutral detergent fiber (NDF), from 515 g kg Ϫ1 for early-harvested tests to 656 g kg Ϫ1 for ponent determining quality. They have a digestible and late-harvested tests, and acid detergent fiber (ADF) contents, from an indigestible fraction. Neutral detergent fiber content 310 g kg Ϫ1 for early-harvested tests to 387 g kg Ϫ1 for late-harvested is a measure of the total cell wall fraction. Acid detertests. Protein was low, ranging from 61.5 to 101.0 g kg Ϫ1 . Biomass gent fiber content is a measure of the indigestible fracyields ranged from 10.1 to 16.5 Mg ha Ϫ1 in the barley cultivar tests, tion. When cell wall content of feed is low, increased 7.0 to 18.5 Mg ha Ϫ1 in the spring cereal tests, and 10.8 to 12.2 Mg intake and digestibility by animals is expected. Protein ha Ϫ1 in the winter cereal tests. Although, some exceptions occurred, content is an important feed factor per se, with highforage yield and quality of cereal mixtures were generally intermediate quality feed having a high protein content. Chemical to monocrop production, especially for moisture and fiber content, composition and nutritive value of green plant material suggesting that planting species mixtures could extend the harvest can give useful information about the quality of the period and result in higher-quality silage.resulting silage (Kjos, 1990).Compositionally, legumes are known to have higher protein and lower cell wall fractions but higher lignin ral Development,

Determining which trait(s) or gene(s) to target to improve barley NUE is important and can be facilitated using simplified growth approaches to help determine the NUE phenotype of various genotypes. The genotypes studied showed similar growth and NUE characteristics across field and growth-chamber tests demonstrating that simplified, low-variable growth environments can help pinpoint genetic targets for improving spring barley NUE.

Increasing costs of N fertilizers and the negative impact of excessive N on the environment have made improvement in nitrogen use efficiency (NUE) a desirable goal in barley (Hordeum vulgare L.) breeding. Seventeen replicated trials, each consisting of 15 to 20 genotypes, were performed across different environments in Alberta, Canada from 1998 to 2007 to determine genetic variability in NUE. Further, 25 genotypes were grown at six environments in 2007 for analysis of the pattern of genotypic variation for NUE. Analysis of variance revealed significant effects of genotype and environment on NUE. The majority of the phenotypic variation in NUE was accounted for by genotypic variance and heritability estimates for this trait ranged from 0.5 to 0.86. Genotypes H97097001001, H96014002, ‘Vivar’, and ‘Xena’, were superior in NUE, yielding 47 to 48 kg kg−1 N as compared to about 35 kg kg−1 N yield for the relatively inefficient genotypes. There was no clear distinction between two‐rowed and six‐rowed types in NUE, but rather significant differences were observed among genotypes within each spike‐type group. Reduction in N fertilizer requirements in barley while maintaining yield may be achieved through breeding by targeting increased yield potential in association with higher NUE.

This study was conducted to evaluate the application of carbon isotope discrimination (CID) as a selection criterion for improving water use efficiency (WUE) and productivity of barley (Hordeum vulgare L.) under field and droughtstress conditions in a greenhouse. A total of 54 genotypes were screened for variability in CID under field conditions, while 23 genotypes were evaluated under water-deficit conditions in the greenhouse. A survey of leaf CID of 54 genotypes at two field locations showed more than 2.14& difference between extreme genotypes. Significant (P £ 0.05) genotypic variation was found in WUE and CID that had a negative strong correlation. There was a negative correlation between leaf CID and aerial biomass in the greenhouse and among six-row genotypes in the field. Correlations between leaf CID across field locations and across irrigation regimes in the greenhouse were significant (experiment 1, r = 0.79 and 0.94 for six-and two-row genotypes), suggesting stability of the CID trait across different environments. Overall, these results indicate the potential of leaf CID as a reliable method for selecting for high WUE and productivity in barley breeding programmes in the Canadian prairies. Further work is currently underway to determine heritability ⁄ genetics of leaf CID and application of molecular marker-assisted selection for the traits in barley breeding programmes.

Higher seeding rates reduced kernel size and grain protein levels without compromising malt extract owing to better endosperm modification of the more uniformly sized kernels. Negative effects of higher nitrogen rates on malt quality can be reduced through development of cultivars with improved ability to modify protein during malting.

P. 1999. Prediction of composition and ruminal degradability characteristics of barley straw by near infrared reflectance spectroscopy. Can. J. Anim. Sci. 79: 519-523. The usefulness of near infrared reflectance spectroscopy (NIRS) for the prediction of the nutritive value of straw was examined with 195 samples of barley straw. Excluding lignin, NIRS technique explained 84 to 94% of the variation in chemical components in the validation set. From 69 to 84% of the variation in ruminal degradability characteristics, excluding rate of degradation, was explained by NIRS. With the exception of neutral detergent fiber, accuracies of prediction were not improved when NIRS calibrations were based upon calibration sets containing straw only in contrast with when barley hay and barley silage were included with straw in the calibration set. We conclude that near infrared reflectance spectroscopy is a useful method for predicting chemical composition of straw and estimating its ruminal degradability characteristics.Key words: Barley, straw, near infrared reflectance spectroscopy, in situ, degradability Mathison, G. W., Hsu, H., Soofi-Siawash, R., Recinos-Diaz, G., Okine, E. K., Helm, J. et Juskiw, P. 1999. Prédiction de la composition et de la dégradabilité ruminale de la paille d'orge par spectrométrie de réflectance dans le proche infrarouge. Can. J. Anim. Sci. 79: 519-523. Nous avons observé sur 195 échantillons de paille l'utilité de la spectrométrie de réflectance dans le proche infrarouge (SPIR) pour la prédiction de la valeur nutritive de la paille d'orge. Sauf pour la lignine, la technique SPIR rendait compte de 94 % de la variation affectant les composants chimiques des échantillons de validation. En outre, elle expliquait de 69 à 84 % de la variation des paramètres de dégradabilité ruminale,sauf le taux de dégradation. À l'exception de la teneur en FDN, le degré de précision des prédictions n'était pas amélioré lorsque les calibrations SPIR étaient basées sur le jeu d'échantillonsde calibration ne contenant que de la paille seule plutôt qu'un mélange de paille et de foin et d'ensilage d'orge. La spectrométrie de réflectance dans le proche infrarouge se présente donc comme une méthode intéressante pour prédire la composition chimique de la paille et pour estimer ses paramètres de dégradabilité dans le rumen. Mots clés:Orge, paille, SPIR, spectrométrie de réflectance dans le proche infrarouge, in situ, dégradabilitéThe majority of wintering beef cow diets in Western Canada contain straw as a result of direct inclusion in rations or because cows obtain it by eating bedding. Methods for measurement of nutritive value of straw are important since it varies in its nutritive value (Mathison et al. 1999). The in situ procedure has been widely used to estimate the nutritive value of feeds for ruminant animals. von Keyserlingk and Mathison (1989) reported that up to 86 and 92% of the variation in voluntary dry matter (DM) intake and digestibility, respectively, could be explained by differences in in situ degradation chara...

Juskiw, P. E. and Helm, J. H. 2003. Barley response to seeding date in central Alberta. Can. J. Plant Sci. 83: 275-281. Seeding date is an important factor influencing productivity of barley (Hordeum vulgare L.). When conditions are conducive to early seeding or result in delayed seeding, producers need to know how cultivars will respond to these seeding situations. In this study, five cultivars (Abee, Harrington, Jackson, Noble and Virden) registered for western Canada were studied for 4 yr (1990 to 1993) when seeded early (late April or early May), in mid-May, in late-May, or late (mid-June) at Lacombe, AB. For all cultivars, early seeding resulted in grain yield advantages of 113 to 134% of the mean site yield, while with late seeding, grain yields were reduced to 54 to 76% of the mean site yield. The reduction in yield was least for Jackson, the earliest maturing cultivar tested. Late seeding reduced the period from sowing to emergence, vegetative period, grain-filling period, time from emergence to physiological maturity, test weight, grain yield, kernel weight, and tillers per plant; and increased plant height and percent thins. Late seeding had no significant effect on phyllochron, stand establishment, scald, lodging, protein content of the grain, kernel number per spike, and spikelet number per spike. Barley responded positively to early seeding in central Alberta, but when seeding was delayed (in this study to mid-June) the early and mid-maturing six-rowed cultivars with short phyllochrons performed better than the two-rowed and late six-rowed cultivars.Key words: Hordeum vulgare L., seeding rate, phenological development, grain quality, grain yield, components Juskiw, P. E. et Helm. 2003. Réaction de l'orge à la date des semis dans le centre de l'Alberta. Can. J. Plant Sci. 83: 275-281. La date des semis influe considérablement sur le rendement de l'orge (Hordeum vulgare L.). Quand les conditions autorisent des semis hâtifs ou retardent ces derniers, il est essentiel de savoir comment les cultivars réagiront. Dans le cadre de cette étude, les auteurs ont examiné cinq cultivars (Abee, Harrington, Jackson, Noble et Virden) homologués pour l'ouest du Canada pendant quatre ans (de 1990 à 1993) et semés hâtivement (fin avril ou début mai), à la mi-mai, à la fin de mai ou tardivement (mi-juin) à Lacombe (Alberta). Les semis hâtifs augmentent le rendement grainier de tous les cultivars de 113 à 134 % comparativement au rendement moyen à cet endroit tandis que les semis tardifs le diminuent de 54 à 76 %. La baisse de rendement était la moins forte pour Jackson, le cultivar le plus précoce. Les semis tardifs réduisent le laps de temps entre la mise en terre et la levée, la période de croissance, la période de remplissage du grain, le laps de temps de la levée à la maturité physiologique, le poids spécifique, le rendement grainier, le poids de l'amande et le nombre de talles par plant; ils augmentent la hauteur du plant et le pourcentage d'éclaircissage. Les semis tardifs n'ont aucune incidence sensible sur le...