bluuebunny/crossref_metadata_2025 huggingface dataset:
A COMPARATIVE STUDY OF CONVENTIONAL, LEAFLESS AND SEMI-LEAFLESS PHENOTYPES OF PEAS: PHOTOSYNTHETIC CO2 FIXATION IN VITRO
Authors: LAFOND G. , EVANS L. E.
Published: March 2010

The effect of the "leafless" mutations (in which tendrils replace leaflets, af, and the stipules are reduced to a vestigial form, st) upon chlorophyll content, total protein, soluble protein, ribulose biphosphate carboxylase activity, and fresh weight/dry weight ratio were studied. Comparison of three near-isogenic lines of Century, Freezer and Trapper for the genotypes af af st st (leafless), af af + + (semi-leafless) and + + st st (reduced stipules) were compared with the conventional (+ + + +) plants. Chlorophyll contents were reduced by as much as 50% in the leafless phenotypes, as compared to the leafed plants. The leafless phenotype showed significantly higher levels of total nitrogen than the leafed plants. Tendrils had significantly lower levels of soluble protein than leaflets in two of the three cultivars examined. The fresh weight/dry weight ratio was significantly higher in the leafless phenotypes than the leafed types as a result of changes in morphology, going from a leaflet to a tendril. The internal arrangement of cells in the tendril was typical of pith and cortex tissue with very few intercellular spaces between the parenchyma cells. The intercellular space index within the tendrils was significantly lower than in the leaflet. In vitro measurements of ribulose biphosphate carboxylase activity were calculated per unit fresh weight and per unit chlorophyll. No significant differences were found between the different phenotypes per unit fresh weight; however, when the activity was measured per unit chlorophyll, the values for tendrils were significantly higher than for leaflets.
ELROSE BARLEY
Authors: HARVEY B. L. , ROSSNAGEL B. G.
Published: March 2010

Elrose is a two-rowed malting barley developed at the Crop Science Department, University of Saskatchewan from the cross KlagesS7122. Its main attributes are the combining of the quality of Klages with the early maturity of Betzes. It is adapted to the traditional two-rowed barley area of west central Saskatchewan and southern Alberta.
DETERMINATION OF TRIALLATE RESIDUES IN ALFALFA AND COMPANION CROPS OF WHEAT AND BARLEY
Authors: CESSNA ALLAN J.
Published: March 2010

Triallate residues were determined in forage samples of both alfalfa and companion crops of wheat and barley which had been treated with preplant incorporations of triallate and grown either under irrigation or dryland conditions. All the samples, collected at the earliest date that the crop would be cut for forage, contained less than 20 ppb triallate, the limit of detection of the analytical method.
DELHI 76 BRIGHT TOBACCO
Authors: WHITE F. H. , PANDEYA R. S.
Published: March 2010

Delhi 76 is a new bright (flue-cured) tobacco (Nicotiana tabacum L.) with superior yield, reduced ground sucker development, better quality, more easily cured leaf and higher disease tolerance than Delhi 34, the presently recommended flue-cured cultivar in Ontario. It was licensed on 19 Nov. 1976. Breeder seed of Delhi 76 is maintained by Agriculture Canada, Research Station, Delhi, Ontario.
THE INFLUENCE OF INTER-PLANT COMPETITION ON THE MORPHOLOGICAL DEVELOPMENT OF SPIKES OF NON-TILLERING BARLEY (Hordeum vulgare L. emend. Lam.)
Authors: BADRA A. , KLINCK H. R.
Published: March 2010

Tweaked and branched rachises are important morphological abnormalities affecting the number of spikelets per spike in uniculm barley. Five uniculm strains and two multiculm cultivars were tested at three seeding dates and nine plant densities involving different spatial arrangements. Significant differences were observed in the mature spikes between uniculm strains and multiculm cultivars, and between uniculm strains. The highest plant densities developed the lowest percentage of spike abnormalities. A significantly lower percentage of abnormalities occurred in material from the earliest seeding date. In a second experiment using the same genotypes, seeding dates and plant densities, it was found that tweaked and/or branched rachises found in the mature plant started to become visible during the first few weeks of seedling development. The development of these abnormalities seems to be influenced by temperature and plant density.
EFFECT OF Phytophthora megasperma ON YIELD AND SURVIVAL OF RESISTANT AND SUSCEPTIBLE ALFALFA CULTIVARS
Authors: FARIS M. A. , SABO F. E.
Published: March 2010

Performance of some artificially inoculated Phytophthora root rot (PRR) resistant and susceptible alfalfa cultivars was determined under field conditions at the Central Experimental Farm, Ottawa. Yields of both resistant and susceptible cultivars were reduced after inoculation; however, the resistant cultivars outyielded the susceptible ones. The resistant, inoculated cultivars showed less winterkill. There is still a need for improving PRR resistance in alfalfa, and thus increasing yield potential.
NORBERT BARLEY
Authors: METCALFE D. R. , BENDELOW V. M.
Published: March 2010

Norbert is a two-rowed spring barley developed at the Agriculture Canada Research Station. Winnipeg, Manitoba from a cross involving C.I. 5791, Parkland, Betzes. Piroline, Akka, Centennial and Klages. It is resistant to stem rust and net blotch, and tolerant to barley yellow dwarf virus. It has excellent straw strength and a large plump kernel and is adapted to Manitoba and eastern Saskatchewan where it has a yield advantage over barley cultivars currently being grown in that region. Norbert has good malting and brewing properties.
NORGOLD — A LOW COUMARIN YELLOW BLOSSOM SWEETCLOVER
Authors: GOPLEN B.P.
Published: March 2010

Norgold is the first low courmarin (LC) cultivar of yellow blossom sweetclover (Melilotus officinalis (L.) Lam.). It was developed at the Agriculture Canada Research Station at Saskatoon as the culmination of a 22-yr breeding program. Norgold produces 16% more forage than Polara, the only other LC cultivar available.
INFLUENCE OF MOWING AND TILLER ORIENTATION ON LEAF MEASUREMENTS OF KENTUCKY BLUEGRASS
Authors: EGGENS J. L.
Published: March 2010

When 11 Kentucky bluegrass (Poa pratensis L.) cultivars were mowed at 2, 3, 4 or 5 cm, the sheath length, blade length and blade width of the third youngest leaves of prostrate (0–29°) tillers were each found to be significantly larger than corresponding leaf parts from intermediate (30–59°) and upright (60–90°) tillers. Corresponding differences were not observed in unmowed grasses.
ETUDE COMPARATIVE DE LA DURETE DU BLE DE PRINTEMPS LAVAL-19 ET DES BLES Triticum aestivum
Authors: KAMARA L. , BOUDREAU A. , CASTAIGNE F.
Published: March 2010

The examination of ultra-thin sections by the scanning electron microscope was performed comparing spring wheat Laval-19 with several types of wheat of increasing hardness (Yorkstar, Concorde and Neepawa) using both whole kernels and the corresponding flours. The hardness properties of each type of wheat was determined using an Instron Tensile Testor. In hard wheats, we observed a tightly packed structure showing little or no air space in the endosperm. The adhesion between proteins and starch granules was strong enough to break the starch granule rather than to separate at the interface. The soft wheats appeared to have a much looser structure with many intergranular air spaces and no broken starch granules. The microscopy of the flours illustrated the integrity of the starch-protein matrix in the hard flours and a mixture of free starch granules, free protein, and small aggregates of protein and starch in soft flours. The Instron measurements were in agreement with the microscopic examination and both techniques indicated clearly the differences in hardness between soft and hard, leaving the spring wheat Laval-19 a type of wheat intermediary between soft and hard.
WATER USE EFFICIENCY OF THREE HEIGHT ISOLINES OF SORGHUM
Authors: OWONUBI J. J. , KANEMASU E. T.
Published: March 2010

Dwarfing of tall sorghums (Sorghum bicolor, L.) provides lodging resistance and adapts the crop to mechanical harvesting. The effect of height on water use and yield are not well known. To help explain the effect of height on water use efficiency (WUE), we compared total water use, photosynthetic light interception, and dry matter accumulation of three height isolines of sorghum in three stands — pure, mixed and alternating rows. Other measurements included leaf temperature, stomatal resistance, and xylem-water potential. Tall plants, which had the highest evapotranspiration in both seasons, also had the highest WUE for dry matter; but the dwarf plants were more efficient with respect to grain water use. Total dry matter yields were in direct relation to the isoline heights. Dwarf plants consistently had the warmest canopy temperature of the isolines during peak insolation periods. Regression of dry matter production on normalized transpiration gave a slope factor (k) of 0.173, 0.222 and 0.296 mb for the double-dwarf, dwarf, and tall isolines, respectively. Photosynthetically active radiation (PAR) interception in the double-dwarf canopy was lower than in other plots. Fewer tillers and loose leaf arrangement on the tall plants allowed higher PAR transmission and, therefore, lower PAR interception compared with the dwarf canopy, though the differences were not statistically significant. Differences in dry matter accumulation among plots were mainly in the stem fraction; tall plants produced about the same quantity as the mixed and alternated plots. The dwarf, with its lower dry matter, produced the most grain in both seasons. Tall plants yielded more grain in the mixed, than in pure or alternated canopies. The short, double-dwarf plants in mixed plots were shaded and, therefore, yielded considerably less dry matter and grain.
FIELD SPECTRAL REFLECTANCE MEASUREMENTS OF SMALL GRAIN CROPS
Authors: GLICK H. L. , LACROIX L. J. , BELL W. C. , SHAYKEWICH C. F. , BRACH E. J.
Published: March 2010

Vertical and oblique measurements of spectral reflectance (0.35–0.75 μm) were made from wheat, barley, oats, sod and fallow plots in a replicated field experiment. Comparisons of reflectance were made to determine the potential for discriminating between these crop types in situ by field spectroscopy. The potential for discrimination was greater when the crops were viewed obliquely. Fallow treatments could be discriminated from cereal crops throughout the season at both viewing angles. Sod treatments could be discriminated from cereal crops at the preboot and anthesis stages of growth. Discrimination amongst wheat, oats and barley was possible as early as 24 days after seeding and was greatest at anthesis. The potential for discrimination amongst these crop types was low after anthesis. The results indicate that crop discriminability is a function of the vertical viewing angle, plant maturity and wavelength of measurement.
EFFECTS OF EIGHT THREE-CUT HARVESTING SCHEDULES ON PRODUCTION OF ALFALFA FORAGE UNDER IRRIGATION IN SOUTHWESTERN SASKATCHEWAN
Authors: IRVINE R. B. , McELGUNN J. D.
Published: March 2010

Harvesting a third cut of alfalfa in southwestern Saskatchewan has not been a normal practice since winter injury often results. This experiment was designed to determine if a third cut could be obtained without inducing injury or reducing yield the following year. The cultivars Roamer and Beaver were planted in two separate years in a nested design with the subplots being nine cutting schedules. A third cut of alfalfa could be harvested after 1 Oct. without reducing the yield of the first cut in the subsequent year. As the time interval between the first and second cuts increased so did the yield. There was a high degree of variability due to harvest years and this was particularly evident on the third cutting dates. The best three-cut system involved two cuts at the recommended 10% bloom stage and a third cut after growth had ceased in October.
CHANGES IN THE LEVELS OF PROTEOLYTIC ENZYMES IN ENSILED ALFALFA FORAGE
Authors: McKERSIE B. D. , BUCHANAN-SMITH J.
Published: March 2010

The activities of several proteolytic enzymes were quantified in ensiled alfalfa (Medicago sativa) forage and their activities were related to proteolysis in the ensiled crop. The enzymes studied were carboxypeptidase at pH 5.2, aminopeptidase at pH 7.0, and acid proteinase against hemoglobin at pH 4.5 and azocasein at pH 5.5. Proteolysis, which was measured as the increase in trichloroacetic acid-soluble, non-protein nitrogen, occurred during the first 1–2 days after ensiling. Silage pH was above 5.5 during the time period of proteolysis. The rate of proteolysis in the ensiled herbage was approximately 25 μmoles amino acid released per gram dry weight per hour, and can be accounted for by the activity of proteolytic enzymes in alfalfa herbage without consideration of microbial enzymes. The activity of the alfalfa proteolytic enzymes declined with time after ensiling, but each enzyme declined independently. For example, the proteinase at pH 4.5 was inactive after 2 days whereas carboxypeptidase retained 45% of its activity even at 21 days after ensiling. The cessation of proteolysis after 2 days ensiling was not due to the lack of proteolytic enzyme activity nor was pH completely inhibitory. The results are further discussed in regard to the regulation of proteolysis during ensiling.
BEEF PRODUCTION FROM GRASS-ALFALFA PASTURES GROWN IN DIFFERENT STAND PATTERNS IN A SEMIARID REGION OF THE CANADIAN PRAIRIES
Authors: KILCHER M. R.
Published: March 2010

Russian wild ryegrass (Elymus junceus Fisch.) and alfalfa (Medicago media Pers.) pastures seeded in mixed rows, or in alternate rows, or in a cross-seeded pattern were grazed by cattle from 1974 to 1980 at Swift Current, Saskatchewan. The legume persisted when seeded alone in the two component separation patterns but had declined to only 15% in the mixed row stands. Daily liveweight cattle gains were largest from the cross-seeded pastures. On a land unit basis, the beef production from cross-seeded pastures was higher than alternate row pastures by 13% and mixed row pastures by 17%. The checkered pattern from cross seeding reduced runoff and erosion by water. No incidence of bloat occurred.
IN VITRO PROPAGATION OF RUTABAGA ROOTPIECES
Authors: GRANT I. , HARNEY PATRICIA M.
Published: March 2010

A basal medium consisting of inorganic salts, 100.0 mg/L myo-inositol, 0.4 mg/L thiamine HCl, 100.0 mg/L casein hydrolysate, 30.0 g/L sucrose and 7.0 g/L agar, supplemented with IAA (1.0 mg/L), BAP (4.0 mg/L) and 2-iP (4.0 mg/L) will induce the regeneration of shoots from rootpieces of rutabaga after a 30-day culture period. Newly regenerated shoots were transferred onto a rooting medium consisting of basal medium supplemented with NAA at 0.5 mg/L. Roots were differentiated in 2–3 wk after which time the plantlets were transplanted into a soil mix.
LEADER HARD RED SPRING WHEAT
Authors: PAUW R. M. De , McBEAN D. S. , BUZINSKI S. R. , TOWNLEY-SMITH T. F. , CLARKE J. M. , McCAIG T. N.
Published: March 2010

Leader hard red spring wheat (Triticum aestivum L.) combines resistance to the wheat stem sawfly with a low level of alpha-amylase activity. It is adapted to the Brown soil zones of Alberta and Saskatchewan.
HERITABILITY OF N2(C2H2) FIXATION RATES AND RELATED CHARACTERS IN PEAS (Pisum sativum L.)
Authors: HOBBS S. L. A. , MAHON J. D.
Published: March 2010

To study the genetic variability of N2(C2H2) fixation rates in peas, 85 genotypes were screened in the field. Genotype means differed (P < 0.01), and ranged from 1.5 to 12.5 μmoles C2H2∙h−1∙plant−1 and from 10 to 49 μmoles C2H2∙h−1∙(g nodulated root)−1. Under environmentally controlled conditions the rankings of six genotypes, selected to represent the full genotypic range of fixation, were significantly correlated to those in the field. A diallel mating design among the six genotypes showed that heterosis occurred in fixation per plant, probably partly due to nonallelic interaction. In fixation per gram nodulated root, however, nonadditive effects were small. Heterosis occurred in total shoot N and in shoot weight, probably due in the latter case to both nonallelic interaction and overdominance. Total dominance, associated with decreased expression, was evident for percent shoot N. Study of the genes controlling fixation may best be done by examining N2(C2H2) reduction on a per-gram nodulated root basis because results are less affected by the genetics of correlated whole plant characters. Fixation expressed in this way might be improved by simple selection.
EFFECT OF SEEDING RATE ON GRAIN YIELD, STRAW YIELD AND HARVEST INDEX OF EIGHT SPRING WHEAT CULTIVARS
Authors: BAKER R. J.
Published: March 2010

Eight cultivars of spring wheat, Triticum aestivum L., were evaluated at seeding rates of 110, 270 and 430 seeds/m2 in a total of nine experiments spanning three locations, two dates of seeding and 2 yr. Grain yield exhibited a significant cultivar × experiment × linear response to seeding rate interaction. Grain yield of Pitic 62 showed a significant decrease with increased seeding rate in one experiment while giving the greatest increase in another. Over all experiments, the highest seeding rate gave the highest grain yield. For straw yield, Chester showed the greatest response to seed rate, Canuck the least. With the exception of Canuck, which showed a significant increase in harvest index with increased seeding rate, harvest index tended to be greater at the intermediate seeding rate.
SINGLE GENE CONTROL OF SEED COLOR AND HYPOCOTYL COLOR IN TURNIP RAPE
Authors: HAWK J. A.
Published: March 2010

The association between hypocotyl color and seed color in turnip rape (Brassica campestris L.) was investigated in crosses of a green hypocotyl, yellow-seeded stock with an early flowering wild-type stock and the Torch cultivar. A complete association was noted between seed color and hypocotyl color. These data are consistent with the hypothesis that a single recessive gene may block pigment production in both hypocotyl and seed. The relevance of this information for breeding yellow-seeded turnip rape cultivars is discussed.
EXPRESSION OF RL 4137 TYPE OF DORMANCY IN F1 SEEDS OF RECIPROCAL CROSSES IN COMMON WHEAT
Authors: NOLL J. S. , DYCK P. L. , CZARNECKI E.
Published: March 2010

Germination of F1 seeds of reciprical crosses between dormant RL 4137 and four less-dormant cultivars of Triticum aestivum L. was compared. Significant reciprocal differences were obtained in all four crosses. The F1 seeds having RL 4137 as the maternal parent were more dormant than the reciprocals, indicating that the seed coat and/or endosperm have a significant influence on seed dormancy. The embryo component of seed dormancy was partially dominant since the F1 seeds with RL 4137 as pollen parent were more dormant than seeds of the less-dormant parents. The degree of dominance in the F1 seeds varied among the crosses. A selection procedure for the development of a sprouting resistant cultivar through backcrossing is discussed.
IN VIVO UTILIZATION OF WILTED GRASS SILAGES PREPARED IN THE MARITIME PROVINCES OF CANADA
Authors: NARASIMHALU P. , WINTER K. A. , KUNELIUS H. T.
Published: March 2010

Voluntary intakes and apparent digestibilities of wilted grass silages produced under humid climatic conditions of the Maritime Provinces of Canada were determined from feeding trials with wether lambs during two 24-day periods. The silages included seeding year Italian ryegrass (Lolium multiflorum Lam. ’Lemtal’), and first-cut perennial ryegrass (L. perenne L. ’Norlea’), meadow fescue (Festuca pratensis Huds. ’Trader’), orchardgrass (Dactylis glomerata L. ’Tardus’), and quack-grass (Agropyron repens (L.) Beauv.). Second-cut quackgrass was also included. Dry matter and digestibile energy intakes were not different among the first-cut silages (58.8–65.7 g and 746–848 KJ/kg.75BW, respectively) but were higher (P < 0.05) in comparison to the intakes of the nutrients contained in the second-cut quackgrass silage (49.6 g and 467 KJ/kg.75BW). The two-stage in vitro dry matter disappearance, but not the acid-pepsin solubility determinations on the silage samples dried at 55 °C, were closely correlated with the intakes of silage dry matter (r = 0.90, P < 0.05) and digestible energy (r = 0.98, P < 0.01), and with the apparent digestibilities of these respective nutrients (r = 0.92 and 0.96, P < 0.01). Silage content of acid detergent fiber, in comparison with in vitro dry matter disappearance, was less closely correlated with the apparent digestibilities of dry matter (r = −0.82, P < 0.05) and digestible energy (r = -0.75, P < 0.10).
ÉTUDES SUR LA BIODÉGRADATION DE LA MATIÈRE SÈCHE DES FOURRAGES PAR LES MÉTHODES IN VITRO ET DES SACS DE NYLON
Authors: CÔTÉ M. , SEOANE J. R. , GERVAIS P. , McQUEEN R. E.
Published: March 2010

Rumen degradation of seven cultivars of timothy and one of bromegrass was studied by the in vitro and the nylon bag techniques. The timothy cultivars were the early maturing Basho, Champ and Toro, the intermediate-maturing Climax, Itasca and Timfor and the late-maturing Bounty. The Saratoga bromegrass was early maturing. All plant material was harvested at two stages of maturity; full head emergence and anthesis. Nitrogen content of forages decreased with advance in maturity, but cell walls (NDF), lignocellulose (ADF) and lignin (ADL) values were not significantly affected. At both stages, bromegrass contained more nitrogen than the timothies. Of all cultivars, Bounty was among those showing the highest values and Saratoga the lowest ones in ADF and ADL. Rumen degradation of dry matter estimated by the nylon bag technique was not different between cultivars; however, differences were detected (P < 0.05) using the in vitro method at anthesis. In vitro dry matter degradation of bromegrass was greater than that of timothy. Among timothy cultivars, Climax was degraded the least. Rumen degradation of all cultivars decreased with advancing maturity of the plant. Of the two techniques, the in vitro method showed more precision than the nylon bag technique and could be used to detect small differences such as those existing between cultivars of the same species. Prediction of rumen degradation of timothy hays from the chemical composition of the plant appeared to follow a curvilinear rather than a linear regression model.
A RAPID METHOD FOR DETERMINING CYANIDE POTENTIAL IN SASKATOON (Amelanchier alnifolia)
Authors: MAJAK W. , PINK B. , HALL J. , McKENZIE J. S.
Published: March 2010

A new method was developed that facilitates the release and determination of hydrogen cyanide from saskatoon tissue. Shrub parts are ground in dry ice and incubated for 1 h in a buffered solution containing hydrolytic enzymes. The incubation mixture is then analyzed directly thereby eliminating the requirement for cyanide distillation or microdiffusion. The method was used to determine the cyanide potential in buds, leaves, twigs and fruit of 24 saskatoon selections, potentially suitable for commercial production. In agreement with previous studies, the results indicate that vegetative parts of saskatoon are potentially hazardous to ruminants but the fruit can be considered innocuous.
INTERACTION BETWEEN DIFENZOQUAT AND PROPANIL OR PROPANIL/MCPA COMBINATIONS FOR WILD OAT AND GREEN FOXTAIL CONTROL IN BARLEY
Authors: SHARMA M. P. , BORN W. H. VANDEN
Published: March 2010

Tank mixtures of difenzoquat and propanil or propanil/MCPA were evaluated for the control of wild oats (Avena factua L.) and green foxtail (Setaria viridis (L.) Beauv.) in a single spray operation. Both propanil and propanil/MCPA reduced the efficacy of difenzoquat on wild oats, but the efficacy of propanil or propanil/MCPA on green foxtail was not adversely affected. Barley (Hordeum vulgare L.) tolerance to the tank mixture was lower than to either of the components of the mixture. Uptake of 14C-difenzoquat by wild oats was reduced markedly in the presense of propanil and propanil/MCPA. If the herbicides were applied separately, the reduction in uptake depended on the extent of overlap of droplets of the two spray preparations on the leaf surface. There was no evidence of a chemical change in difenzoquat in the tank mixes, but the observed separation of components of the mixture soon after mixing may be partly responsible for the reduced uptake. We conclude that the marked inhibition of difenzoquat uptake in the presence of propanil or propanil/MCPA plays an important role in bringing about the antagonism between these herbicides.
MAPLE PRESTO SOYBEANS
Authors: VOLDENG H. D. , SEITZER J. F. , DONOVAN L. S.
Published: March 2010

Maple Presto is the earliest maturing soybean (Glycine max (L.) Merr.) cultivar licensed in Canada. It combines with earliness the attributes of high oil content in the seed, resistance to lodging and shattering, and adequate plant height.
VIGOR OF SEEDS FROM TOMATO PLANTS GROWN UNDER VARIOUS LEVELS OF WEED INTERFERENCE
Authors: LIPTAY A. , FRIESEN G. H.
Published: March 2010

Fruits from tomato plants grown under continuously weedy conditions had a significantly greater percentage of seeds with high vigor than those from weed-free plots. Germination percentage was not affected by any of the weed-interference treatments but overall germination percentages differed from year to year.
WATER STRESS OF ALFALFA DURING STRESS AND RECOVERY
Authors: HALL ROBERT G. , LARSON KENNETH L.
Published: March 2010

Water status and stomatal activity of alfalfa (Medicago sativa L.) cultivars Cody and Sonora were evaluated under greenhouse conditions during water stress and recovery at the 7th leaf and full bloom developmental stages. Following onset of stress predawn LWP declined linearly and plants remained visibly wilted as potentials approached 1.8 MPa in both cultivars and developmental stages. Significant (P = 0.05) relationships were evident between predawn LWP and days after onset of stress (R2 > 0.90) and between daily maximum leaf conductance (KL) and predawn LWP (R2 > 0.80) when averaged over both cultivars at each stage. Recovery of LWP of both cultivars was complete within 24 h after rewatering. Ability of stomatal activity to recover was similar for both cultivars and developmental stages and was attained within 32 h after rewatering. Results indicate that these cultivars, which differ in winterhardiness, do not differ in water status and stomatal activity with increasing water deficits.
RESPONSE OF THREE WARM-SEASON GRASSES TO VARYING FERTILITY LEVELS ON FIVE SOILS
Authors: TAYLOR R. W. , ALLINSON D. W.
Published: March 2010

Animal production in New England has been limited by inadequate forage during mid- to late summer when cool-season grasses are in summer dormancy. Big bluestem (Andropogon gerardi Vitman), indiangrass [Sorghastrum nutans (L.) Nash] and switchgrass (Panicum virgatum L.) are warm-season grasses that may be a perennial source of summer forage. Since production of these warm-season grasses would be limited to the less fertile soils of the region, a greenhouse study was conducted to examine the growth and quality of these species in five acid, infertile soils as well as fertilizer-amended soils. The soils were fertilized with limestone (L), limestone plus nitrogen (LN), limestone, nitrogen plus phosphorus (LNP), and limestone, nitrogen, phosphorus plus potassium (LNPK). Limestone was applied to adjust soils to a pH of 6.5. Fertilizer was applied at rates of 45, 117 and 111 kg/ha of N, P and K, respectively. First harvest yields were greatest for switchgrass and big bluestem, but indiangrass produced significantly greater yields than either of the other grasses in the second harvest. In both harvests, the yields of all grasses were greatest under the LNP and LNPK fertility regimes. Nitrogen, without P, did not significantly increase yields above the control treatment in the first harvest. Yield responses to P fertilization varied with soils. Although P appeared to be the limiting factor insofar as growth was concerned, the yield response from P fertilization would probably be limited without N fertilization. Indiangrass was significantly higher in crude protein and K concentration and significantly lower in Ca concentration than big bluestem and switchgrass. Phosphorus concentrations were below the recommended levels for ruminant nutrition.
EFFECTS OF VEGETATION SUPPRESSION AND DRILLING TECHNIQUES ON THE ESTABLISHMENT AND GROWTH OF SOD-SEEDED ALFALFA AND BIRD’S-FOOT TREFOIL IN GRASS DOMINANT SWARDS
Authors: KUNELIUS H. T. , CAMPBELL A. J. , IVANY J. A. , MCRAE K. B.
Published: March 2010

The sod seeding of alfalfa (Medicago sativa L.) and bird’s-foot trefoil (Lotus corniculatus L.) was studied in three locations previously cut for conserved feed or used for pasture. At each location an experiment with a split-split-plot design was established with sod-seeded alfalfa and bird’s-foot trefoil as main treatments, methods of drilling as subtreatments, and methods of vegetation control as sub-subtreatments. Drilling was done with a John Deere PowrTill 1500 renovator and Øyjord plot drill equipped with shoe openers. The methods of vegetation control included mowing and spraying with 1:1-′dimethyl-4.4′bipyridinium dichloride (paraquat) or N-(phosphonomethyl) glycine (glyphosate) at the time of drilling. Sod seeding alfalfa resulted in greater dry matter yields than bird’s-foot trefoil. Alfalfa and bird’s-foot trefoil constituted 27 and 17% of total yield in the year after sod seeding and 17 and 4% in the 2nd year after drilling, respectively. Alfalfa performed better in a sward previously cut for conserved feed while bird’s-foot trefoil performed better in a field used for pasture. Both PowrTill and plot drill resulted in satisfactory seedling establishment although the yields of sod-seeded legumes were greater with plot drill than with PowrTill in the year after drilling. Vegetation suppression with paraquat and glyphosate did not improve the growth of sod-seeded alfalfa or bird’s-foot trefoil over the unsprayed treatment. In a heavy sward consisting mainly of Poa pratensis L., sod-seeded alfalfa, and bird’s-foot trefoil failed to establish.
EFFECTS OF SURFACE SOIL PH ON SOIL CATION CONTENT, LEAF NUTRIENT LEVELS AND QUALITY OF APPLES IN BRITISH COLUMBIA
Authors: NEILSEN G. H. , HOYT P. B. , LAU O. L.
Published: March 2010

’Starkrimson’ Delicious (Malus domestica Borkh.), 10–15 yr old, on seedling rootstock, were sampled in several orchards, selected for uniformly low soil pH (< 5.0), medium pH and high pH (6.5–7.3). Harrold Red Delicious, 20–25 yr old, were sampled in 18 orchards which had low, medium and high pH within each. Soils with low pH were generally characterized by higher exchangeable Mn and lower exchangeable Ca. Exchangeable soil Mg and K levels were not significantly related to soil pH. On soils of low pH, higher leaf Mn was the main plant nutrient response with both Harrold Red and Starkrimson trees. Significantly decreased leaf Ca was observed on the younger Starkrimson trees at low soil pH. Soil pH had no direct effect on fruit firmness, soluble solids, juice acidity, or flesh Ca, Mg and K contents. Poststorage fruit quality problems were primarily surface scald and were not related to differences in soil pH. Incidence of flesh browning was, however, related to low flesh Ca content.
SEED GERMINATION AND SEEDLING GROWTH CHARACTERISTICS OF ATRAZINE-SUSCEPTIBLE AND RESISTANT BIOTYPES OF Brassica campestris
Authors: MAPPLEBECK L. R. , MACHADO V. SOUZA , GRODZINSKI B.
Published: March 2010

Seed germination and seedling characteristics of atrazine-susceptible and resistant wild turnip rape biotypes (Brassica campestris L.) were examined. Seeds of the susceptible biotype germinated earlier, and the germinated seeds grew faster and emerged earlier than seeds of the resistant biotype. Seedlings of the susceptible biotype emerged from greater planting depths than the resistant seedlings. Emerged susceptible seedlings were larger, with longer hypocotyls and greater cotyledon area, and produced more dry matter than the resistant biotype seedlings. Differences in water content of germinated seeds of the two biotypes were noted, with the susceptible biotypes consistently showing a higher water content. There was no significant difference in the respiration rate of the two biotypes at the early stage of seedling growth.
POLLEN GERMINATION AND CHILLING SENSITIVITY IN TWO TOMATO CULTIVARS OF DIFFERING SENSITIVITY TO COOL NIGHT TEMPERATURE
Authors: HUNER N. P. A. , HUYSTEE R. B. VAN
Published: March 2010

The effect of low night temperature on pollen tube formation and chilling sensitivity was compared in two tomato cultivars, Ontario 7515, free-setting at low temperature, and Ohio MR13, poor-setting at low temperature. The rate and extent of pollen grain germination in the Ontario 7515 cultivar far exceeded that of pollen grains obtained from the Ohio MR13 cultivar. In addition, the rate of pollen tube growth was greater in the free-setting cultivar than the poor-setting cultivar. No major differences were observed in the chilling sensitivity of the vegetative parts of these two tomato cultivars. It is concluded that the differential ability of these two tomato varieties to set fruit during growth at cool, night temperatures may be a function of differential flower production and a differential rate of pollen grain germination rather than a differential chilling sensitivity of the vegetative plant.
EFFECT OF CATTLE GRAZING ON SUBSEQUENT GRAIN YIELD OF FALL RYE (Secale cereale L.) IN SOUTHWESTERN SASKATCHEWAN
Authors: KILCHER M. R.
Published: March 2010

Fall rye grain yields were reduced when grazed during the fall of the seeding year, spring of the succeeding year or when grazed during both the fall and spring periods. Spring grazing reduced grain yield by only 10% and fall grazing by only 17%; grazing in both fall and spring reduced yield by 25%.
HEINRICHS ALFALFA
Authors: IRVINE R. B. , LAWRENCE T.
Published: March 2010

Heinrichs alfalfa (Medicago media Pers.) was developed at the Agriculture Canada Research Station at Swift Current. This erect-growing, hay-type cultivar is as winterhardy as Rambler and produces 10% more dry matter.
ENVIRONMENTAL EFFECTS ON SEED SET IN OILSEED SUNFLOWER (Helianthus annuus L.)
Authors: ROATH W. W. , MILLER J. F.
Published: March 2010

Incomplete seed set of certain commercial sunflower hybrids may be caused by self-incompatability, partial fertility restoration, or other factors which could be affected by the environment. Three commercial hybrids and their fertile inbred parents were planted at five locations across the central plains area of the U.S. during 1978 and 1979. Relative number and weight of developed seed were determined from six of these environments. Little difference in seed set was observed between bagged and unbagged heads of two of the hybrids and their inbred parents. The bagged heads of the third hybrid and its B-line inbred parent had consistently lower seed set. Environment affected seed set significantly. The number of developed seed in percent was consistently less than the weight of viable seed in percent.
CHLOROPHYLL ANALYSIS OF WHOLE RAPESEED KERNELS BY NEAR INFRARED REFLECTANCE
Authors: TKACHUK RUSSELL , KUZINA F. D.
Published: March 2010

Chlorophyll content was determined in whole rapeseed samples, from Regent and Candle cultivars, by using a reflectance technique in the visible and near infrared region. Chlorophyll content was estimated with good accuracy when predicted results for 42 samples of Regent, 37 samples of Candle and 79 samples for both cultivars combined were compared with standard laboratory results. For Regent, a multiple correlation coefficient (R) of 0.944 and a standard error of estimate (Sy) of 4.7 were obtained when reflectance was measured at six wavelengths. For Candle, R = 0.963 and Sy = 4.4, using another six wavelengths. For both cultivars combined, R = 0.939 and Sy = 4.8, again using a different set of six wavelengths. Wavelengths for predicting chlorophyll were selected from the 630-to 754-nm visible region, and from the 1640- to 2176-nm near infrared region. This reflectance method described for whole rapeseed is rapid, involves no sample preparation, and leaves the seed intact and available for other uses.
EFFECT OF SEEDING DEPTH, SEEDING DATE AND SEED SIZE ON COMMON ROOT ROT OF SPRING BARLEY
Authors: DUCZEK L. J. , PIENING L. J.
Published: March 2010

The effects of variable seeding depth and dates of seeding of barley on the incidence of root rot, and on emergence and grain yield were investigated in field trials at Saskatoon and Scott, Saskatchewan. The effect of variable seeding depth of barley on intensity of root rot, grain yield, loss of yield due to root rot, and the effect of variable seed size of barley on incidence of root rot and yield were also investigated in field trials at Lacombe, Alberta. Symptoms of common root rot, based on lesions on the subcrown internode, were not influenced by seed size or seeding date but the disease increased with depth of seeding. Grain yield decreased with depth and with late seeding. Emergence was not affected by seeding date but decreased with depth of seeding. Common root rot was not associated with the reduced yields of later seeding dates but was associated with reduced yields of increased seeding depths. The increased emergence and reduced disease at shallow depths resulted in a greater number of clean plants which probably accounts for some of the increased grain yield at shallow seeding depths.
ASSOCIATION BETWEEN GLIADIN ELECTROPHORETIC BANDS AND QUALITY IN COMMON WHEAT
Authors: POGNA N. E. , BOGGINI G. , CORBELLINI M. , CATTANEO M. , PERUFFO A. DAL BELIN
Published: March 2010

Twenty common wheat (Triticum aestivum L.) cultivars were classified into two groups based on the presence or absence in their electrophoregrams of two gliadin bands separated by polyacrylamide gel electrophoresis. The two groups were compared for quality and agronomic characteristics evaluated during 6 yr of testing. The group 1 cultivars (band 40 present, 43.5 absent) had weaker gluten properties and lower loaf volume than cultivars in group 2 (band 40 absent, 43.5 present). No significant difference between the groups was found for protein content or grain yield. The present data are discussed in relation to similar results obtained by other authors for durum wheat cultivars.
AGROCHEMOTAXOMETRY OF ALFALFA
Authors: SMALL ERNEST , LEFKOVITCH L. P.
Published: March 2010

The relationships between 14 agronomically important chemical characteristics and 12 morphological traits were examined in several hundred stocks of alfalfa (Medicago sativa L.) grown in a common plantation. Significant univariate and multivariate associations were found between the percent of S and Ca and the morphological variables. The associations with S could be attributed to relative parentage of ssp. sativa and ssp. falcata, the former showing about 27% higher S content than the latter. Hybrid derivatives between the two subspecies possessed about 24% less Ca, a phenomenon which may be related to the notable adaptive divergence between sativa and falcata with respect to calcareous soil. The two chemical variables had only limited value as taxonomic discriminators of ssp. sativa, ssp. falcata, and populations of hybrid origin.
INDUCTION OF TWO MUTANTS IN BIRDSFOOT TREFOIL (Lotus corniculatus) BY X-RAYS AND CHEMICAL MUTAGENS
Authors: THERRIEN MARIO C. , GRANT W. F.
Published: March 2010

The mutagenic effects of X-rays, ethyl methanesulfonate (EMS), 8-ethoxycaffeine (EOC), N-hydroxyurea (HU) and 2-aminopurine (2AP) on seed treatment of birdsfoot trefoil (Lotus corniculatus L. ’Mirabel’) were assessed over four generations. Mutants were recovered in the M2, M3 and M4 generations from selfed lines, from crosses derived from selfed lines and from open pollination lines. Mutant plants exhibiting vestigial floret character were recovered from X-ray, EMS, EOC and HU treatments. Mutant chlorotica plants were obtained from EMS treatment only. No mutants were recovered from 2AP treatment, EMS, the most effective mutagen, produced nine vestigial floret and 12 chlorotica mutants. Mutants were obtained from only one exposure of X-rays (12 krad). There was evidence for preferential elimination of gametes. The chlorotica and vestigial floret mutants were inherited as tetrasomic recessives. Mutation frequencies of 0.4–3.1% in a tetrasomic background are indicative of the effectiveness of EMS in birdsfoot trefoil.
INFLUENCE OF BORON NUTRITION ON GLUCOSINOLATES AND REDUCING SUGARS OF TURNIP
Authors: JU HAK-YOON , CHONG CALVIN , BIBLE BERNARD B.
Published: March 2010

The influence of six boron treatments (0, 0.1, 0.5, 2.5, 5.0 and 10.0 ppm) on glucosinolates and reducing sugars was studied in tops and roots of hydroponically grown Snow Ball turnip (Brassica rapa L.). The glucosinolates were determined by quantifying their hydrolytic products, 5-vinyl-oxazolidine-2-thione (goitrin), volatile isothiocyanates, and thiocyanate ion. While growth of plants receiving no boron (0 ppm) was drastically impaired, that of plants receiving 0.1–5.0 ppm boron was equally vigorous; growth was slightly inhibited with 10.0 ppm boron. Mild boron deficiency was manifested as brown-heart in roots of fully-sized turnips from the 0.1 ppm boron treatment although there was no apparent effect on external root appearance or on foliage and plant growth. In roots of boron-deficient turnips, elevated yields of goitrin were found, accompanied by relatively high yields of thiocyanate ion and low contents of reducing sugars.
POTENTIAL VEGETATIVE PRODUCTIVITY IN CANADA
Authors: TOLLENAAR M.
Published: March 2010

Duration of the growing season appears to be the single most important factor limiting vegetative productivity in Canada. A theoretical estimate of annual vegetative productivity in the absence of limitations due to water, nutrients or soil structure, shows that potential productivity in the 5-mo growing season of Southern Canada is in the range of 25–55 tonne/ha. Maximum productivity, however, lies considerably below the potential productivity estimate due to lower-than-expected photosynthetic efficiency during periods of high solar irradiance. Crop growth rates appear to be rather independent of variation in radiant flux density during the growing season. Consequently, a realistic estimate of maximum vegetative productivity can be obtained by multiplying number of days of full light interception by a crop canopy, by a crop growth rate of 230 kg∙h−1∙day−1 and adding the weight of the crop at the onset of full light interception by the canopy. Maximum vegetative productivity could likely be improved by extending the period of full light interception by crop canopies through the cultivation of perennial species or double-crop sequences. Alternatively, vegetative productivity could likely be improved through increased photosynthetic efficiency. Very high photosynthetic efficiencies of crops grown under field conditions have been reported occasionally in the literature, but factors underlying this high photosynthetic efficiency have not yet been identified.Key words: Vegetative production, photosynthetic efficiency, potential productivity, duration of growing season, crop species
PLANT-TO-PLANT VARIABILITY OF MAIZE PLANTS GROWN AT DIFFERENT DENSITIES
Authors: DAYNARD T. B. , MULDOON J. F.
Published: March 2010

Development of plant-to-plant variability in plant height, flowering characteristics and grain yield was studied in two maize (Zea mays L.) hybrids grown over 2 yr at 62 000, 93 000 and 124 000 plants/ha. The purpose of the research was to provide fundamental data on patterns of interplant variability in maize, as a foundation for more applied studies on effects of cultural practices on within-crop variability and yield. Plant height was normally distributed early in the season but tended to become negatively skewed as the plants grew. The same tendency for negative skewness existed in calculations of rate of elongation. The standard deviations of height and of rate of elongation increased as plants enlarged. Frequency distributions of days to anthesis or silking were positively skewed as was the distribution of number of days from anthesis to silking at high density. The standard deviations of days to silking, and days from anthesis to silking increased with increasing density. Grain yield per plant was normally distributed or slightly skewed negatively, with barren plants not considered. With the latter included, frequency distributions were bimodal at higher densities. The standard deviation of plant height increased as the crop developed although the coefficient of variability of height declined. Plants which were initially short did not "catch up" in height until after flowering had begun. Taller plants tended to anthese and silk earlier and produce more grain; in general, these associations were stronger with measurements of height taken prior to flowering than after. Date of silking was more closely related to yield than date of anthesis. On average, plants destined to be barren were shorter than the population mean on all dates of measurement and retarded in development. However, many plants became barren which were taller than average and earlier than average in date of flowering.Key words: Competition, maize, barrenness, grains, height, silking
YIELD, QUALITY AND DEVELOPMENT OF FORAGE MAIZE AS INFLUENCED BY DATES OF PLANTING AND HARVESTING
Authors: FAIREY N. A.
Published: March 2010

The effects of dates of planting and harvesting on yield, quality and development of forage maize were investigated in a 3-yr study. Treatments studied were all possible combinations of five planting dates, spaced at 2-weekly intervals from late April to mid-June, and three harvest dates (mid-September, early and mid-October). Between early May and mid-June, each 1-day delay in seeding resulted, on average, in a 1% reduction in whole-plant digestible dry matter yield. In vitro dry matter digestibility was not significantly affected by date of harvesting but was reduced progressively from 66 to 63% as the date of planting was delayed. Although grain content varied from 0 to 50% of whole-plant dry matter, it had little effect on the in vitro digestibility of forage maize, which only ranged from 62 to 68%, when whole-plant dry matter contents were acceptable for direct ensiling. During the grain-filling period (450–1600 corn heat units after mid-silking), whole-plant dry matter content (%) was linearly related to accumulated corn heat units (r2 = 0.83***); each 1% increase in dry matter content requiring an input of 40 corn heat units. Thus, using information on the date of mid-silking and daily air temperature records (long-term or current), it is possible to predict the date (average or actual) when whole-plant DM content reaches any desired magnitude for harvesting.Key words: Quality, planting date, harvest date, maize, corn, development
THE INFLUENCE OF WEAR AND NITROGEN ON CREEPING BENTGRASS GROWTH
Authors: KOHLMEIER G. P. , EGGENS J. L.
Published: March 2010

The effects of nitrogen and wear stress on the growth of Penncross creeping bent-grass (Agrostis palustris Huds.) maintained as a putting green was evaluated from June 1978 to November 1979. The 8-yr-old sward was grown on a Fox sandy loam, mowed five times weekly and irrigated as required. Nitrogen was applied as ammonium nitrate at 1.5, 3.0 and 6 kg N∙100 m−2. Wear treatments, applied for specific periods of time, were zero, three and six passes per day. Turf injury was due to direct wear stress rather than soil compaction as the soil bulk density was unaltered by wear treatment. As wear treatments increased, thatch thickness, clipping yields and healing potential decreased. Electrical resistance measurements of leaf tissue decreased as wear stress increased. This technique provided a rapid and reliable estimate of leaf injury from wear stress. Nitrogen at 3 kg∙100 m−2 increased healing potential, turf greenness and root production over the zero N treatment. However, 6 kg N∙100∙m−2 was excessive. Despite the significant increase in green color, there was no significant increase in healing potential and root growth over the 3-kg rate and the annual bluegrass content of the turf was increased.Key words: Annual bluegrass, thatch, healing potential