bluuebunny/crossref_metadata_2025 huggingface dataset:
An assessment of the concept of early time of weed removal in field pea using natural weed populations
Authors: May W. E. , Lafond G. P. , Johnson E. N. , Hogg T. , Johnston A. M. , Nybo B. , Harker N. , Clayton G.
Published: April 2011

The economic and agronomic benefits of including annual grain legumes in cropping systems has resulted in a large increase in field pea production in Western Canada. Concerns have been raised about the large year-to-year variability in field pea grain yields and recent attention has focussed on weed management. A study was conducted to quantify the effects of time of post-emergence herbicide application to normal leafed and semi-leafless field pea types under natural weed populations and conservation tillage practices. Odyssey™ herbicide (50:50 imazethapyr:imazamox) was applied either 1, 2 or 3 wk after crop emergence with an untreated check included. The study was conducted at seven locations across the major agro-ecological zones of Saskatchewan in 1999 and 2000. The results of this study support the merits of early herbicide application 1 to 2 wk after crop emergence. Benefits of early time of weed removal occurred in 7 of 14 sites-years. There was no yield penalty recorded from early applications of herbicide, but some yield penalty was observed with later applications at certain locations. Spraying early rather than late minimizes the risks associated with delayed applications resulting from adverse weather conditions and a possible decrease in crop tolerance as was observed at the Swift Current site. Results support the early removal of weeds from field pea crops to optimize seed yield. Key words: Crop-weed interference, Pisum sativum L., weed management, timing of herbicide application
Amplified fragment length polymorphism analysis of 96 Canadian oat cultivars released between 1886 and 2001
Authors: Solomon Kibite Yong-Bi Fu, , Richards Ken W.
Published: April 2011

Canadian oat breeders have developed and released more than 130 cultivars since 1886, but no systematic analyses of the genetic diversity of Canadian oat have been made. Ninety-six Canadian oat cultivars released between 1886 and 2001 were examined for genetic diversity and relationships using amplified fragment length polymorphism (AFLP) markers. Ten AFLP primer pairs were applied and over 442 polymorphic bands were generated for each cultivar. Most of the cultivars were found to be interrelated, although a few genetically distinct cultivars were also identified. The genetic variation observed among these cultivars was low. Only 42.8% of the total scorable bands were polymorphic, of which 59 polymorphic bands were observed frequently (f ≥ 0.90) and 130 bands were detected infrequently (f ≤ 0.01) among the 96 cultivars. The mean proportion of fixed recessive bands for all cultivars was high (60.2%) and ranged from 52.3% in cultivar ‘Erban’ to 65.2% in cultivar ‘Glen’. The genetic variability did not change significantly in the Canadian oat breeding programs; only about 1% of the AFLP variation might have been fixed during the 115 years of oat breeding. These findings demonstrate the narrowness of the Canadian oat gene pool and the urgent need to broaden the gene pool for sustainable oat improvement in Canada. Key words: Amplified fragment length polymorphism (AFLP), oat, Avena sativa, genetic diversity, genetic relationship
Carbon isotope discrimination of tall fescue cultivars across an irrigation gradient
Authors: Jensen Kevin B. , Asay Kay H. , Johnson Douglas A. , Waldron Blair L.
Published: April 2011

Carbon isotope discrimination (Δ) has been proposed as an indirect criterion for evaluating water-use efficiency; however, limited information is available regarding the relationship between and dry matter yield (DMY) at different levels of irrigation. Ten cultivars of tall fescue (Festuca arundinacea Schreb.) were established in the field under a line-source irrigation system and defoliated five to six times per growing season. Objectives of our 2-yr study were to evaluate: (i) trends in Δ across a gradient of four water levels (WL-2, wettest to WL-5, driest) at a mid-summer harvest, (ii) the consistency among grass cultivars at one WL across two harvest dates, and (iii) relationships between Δ and DMY within and across water levels. Consistent and significant differences (P < 0.05) were found among cultivars for Δ when evaluated at WL-2 for Harvests 2 and 4 in successive years. Cultivars also differed significantly for Δ (P < 0.01) across four water levels when evaluated at Harvest 4. Relative differences among cultivars were consistent across water levels and between harvest dates. Although a curvilinear trend was evident for some cultivars, mean Δ values decreased in a near linear manner from WL-2 to WL-5. Based on orthogonal polynomials, the mean trend across water levels was partitioned as 95% linear and 5% quadratic. Correlations between Δ and DMY were nonsignificant at the higher water levels (WL-2 and 3), but correlations were positive at the lower water levels (WL-4 and 5). We conclude that under lower water levels, selection for low Δ in tall fescue cultivars will likely lead to decreased forage yield. Key words: Festuca arundinacea, forage yield, water-use efficiency, line source, delta
Cost of crop losses in processing tomato and cabbage in southwestern Ontario due to insects, weeds and/or diseases
Authors: Tolman J. H. , McLeod D. G. R. , Harris C. R.
Published: April 2011

The relative importance of insects, weeds and diseases to yield losses in processing tomato (Lycopersicon esculentum Mill.) and cabbage (Brassica oleracea L. var. capitata L.) was measured by comparing yields in the presence and absence of appropriate control programs. In the absence of any pest control, average crop losses exceeded 80% in both crops. Average yield losses due to weeds alone approached 80% in processing tomato and 60% in cabbage. Insects alone did not significantly reduce yield of processing tomato in either year. In the absence of insect control, significant yield loss in cabbage approached 50% in only one year. When diseases were not controlled, yield of processing tomato declined significantly by nearly 30% in one trial. Failure to control disease had no significant impact on cabbage yield in this study. Monetary losses and costs of each management program were calculated. Key words: Tomato, cabbage, yield loss, insects, weeds, diseases
Response of Aphanomyces euteiches mycelia, zoospore, and oospore to oat extract
Authors: Chandler M. A. , Fritz V. A. , Allmaras R. R.
Published: April 2011

Root rot (Aphanomyces euteiches Drechs.) is a serious economic threat to pea (Pisum sativum L.) production. Research has shown a late-summer-seeded oat (Avena sativa L .) crop can reduce disease severity. A. euteiches was exposed to extracts of oat cvs. Bay and Ogle. Oat extract significantly enhanced mycelial growth of the pathogen. Key words: Root rot, biological control, green manure, Pisum sativum
Evapotranspiration efficiency of pea in south and central Alberta
Authors: McKenzie R. H. , Middleton A. B. , Flore N. , Bremer E.
Published: April 2011

Evapotranspiration (ET) efficiency regulates suitability and management of crops on the Canadian prairies. To evaluate the ET efficiency of pea (Pisum sativum L.), soil water depletion and yields as a function of precipitation were determined for Carneval pea at 28 sites in south and central Alberta from 1995 to 1998. Soil water depletion between seeding and harvest was as high as 112 mm at sites with high levels of available soil water at seeding and low to moderate levels of precipitation. Pea was capable of extracting soil water to a depth of about 0.6 m at most sites, but extraction of soil water below this depth was much more variable. At sites where soil water did not limit the depth of soil water extraction, a negative correlation was observed between the maximum depth of effective soil water extraction and the sum of maximum temperature degree-days above 25.6°C. The ET efficiency of pea seed yield ranged from 7.5 to 19.1 kg ha-1 mm-1, with an average value of 13.0 kg ha-1 mm-1. No correlation was observed between ET efficiency and weather variables, such as average temperature, vapor pressure deficit or length of the growing season. Key words: Pisum sativum, water use efficiency, root depth, drought stress
CDC LeMay lentil
Authors: Vandenberg A. , Vera C. , Buchwaldt L. , Dueck S. , Morrall R. A.A. , Warkentin T. D. , Banniza S. , Slinkard A. E.
Published: April 2011

CDC LeMay is a high-yielding, yellow cotyledon lentil (Lens culinaris Medik.) cultivar developed by the Crop Development Centre, University of Saskatchewan, Saskatoon, Saskatchewan. It is suitable for the French Green market class of lentil and is intended for cultivation in all lentil-growing areas of western Canada. CDC LeMay was issued registration #5552 on October 28, 2002 by the Variety Section, Plant Health and Plant Products Division, Canadian Food Inspection Agency. Key words: Lentil, cultivar description, Lens culinaris
Black Violet common bean
Authors: Ferdinand A. Kiehn Hans-Henning Mündel, , Huang Henry C. , Conner Robert L. , Saindon Gilles
Published: April 2011

Black Violet is a high-yielding, large-seeded, purple-podded, upright black dry bean (Phaseolus vulgaris L.) cultivar. It was developed at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Lethbridge, with cooperation from the AAFC Research Station, Morden. Black V iolet is well adapted to the Canadian prairies, with high yields equal to the high-yielding check cultivar, AC Harblack, in narrow rows. Black Violet is moderately resistant to white mould, caused by Sclerotinia sclerotiorum (Lib.) de Bary; resistant to the Delta race and moderately resistant to race 1216 of anthracnose, caused by Colletotrichum lindemuthianum (Sacc. & Magnus) Lams.-Scrib.; and resistant to race 15 of bean common mosaic virus (BCMV). Key words: Common bean, Common bean, Phaseolus vulgaris, black bean, cultivar description, high yielding
Early Rose pink bean
Authors: Ferdinand A. Kiehn Hans-Henning Mündel, , Huang Henry C. , Conner Robert L. , Saindon Gilles
Published: April 2011

Early Rose is a very early-maturing, high-yielding pink bean (Phaseolus vulgaris L.) cultivar developed at the AAFC Research Centre, Lethbridge, Alberta with final selection and testing carried out at the AAFC Research Station, Morden, Manitoba. Early Rose is particularly well adapted to production in narrow rows across the southern Canadian prairies. Key words: Phaseolus vulgaris, pink bean, cultivar description, early maturing, high yield
Tillage index predicts weed seedling recruitment depth
Authors: Van Acker R. C. , Bullied W. J. , du Croix Sissons M. J.
Published: April 2011

The influence of tillage on the depth of weed seedling recruitment has implications for species competitive ability, weed management strategy development, and the modeling of weed emergence; characterization of this relationship could aid in the creation of field-specific models of weed seedling recruitment. A tillage index based on the percentage of residue cover remaining on the soil surface after tillage events was assessed for 44 zero-tillage and 44 conventional-tillage fields across Manitoba, Canada. This index was related to in situ measurements of seedling recruitment depth from the same fields for five annual weed species. The modeled relationship was linear and unique for each species (R2 values ranged from 0.38 to 0.71). The relationship did not differ between pre- and post-seeding measurements, or between years, except for green foxtail. Slopes of the regression lines were greater for species such as volunteer wheat, which can recruit from a great range of depths. The results of this study show that recent tillage strongly influences mean weed seedling recruitment depth, and that the recruitment depth of summer annual weed seedlings is related in a continuous and reliable manner to a simple estimation of the relative level of tillage (including seeding) applied in one season. Key words: Recruitment depth, tillage index, weed emergence, weed seedlings
Gamma-hydroxybutyrate accumulates in green tea and soybean sprouts in response to oxygen deficiency
Authors: L Allan W. , Peiris C. , Bown A. W. , Shelp B. J.
Published: April 2011

Gamma-hydroxybutyrate (GHB) is an illicit drug, which may be derived in plants from a stress-inducible metabolite known as gamma-aminobutyrate. Here, oxygen deficiency caused the accumulation of GHB in green tea and soybean sprouts (76 and 155 nmol g-1 fresh weight, respectively). These findings demonstrate that GHB levels are elevated in severely modified atmospheres, but they pose no risk to human health. Further work is required to assess the extent of this phenomenon. Key words: Gamma-hydroxybutyrate, gamma-aminobutyrate, oxygen deficiency, tea, bean sprouts
Herbage yield and crude protein concentration of rangeland and pasture following hog manure application in southeastern Alberta
Authors: Blonski Laura J. , Bork Edward W. , Blenis Peter V.
Published: April 2011

Intensive hog production is expanding into semi-arid regions of Alberta, where perennial forage lands are increasingly targeted for manure applicati on despite limited guidelines for its efficient use. Herbage yield and crude protein were assessed over two consecutive years within two native rangelands and two tame pastures, following different rates (10, 20, 40, 80 and 160 kg ha-1 NH4-N), methods (surface banding vs. subsurface injection) and seasons (fall vs. spring) of one-time liquid hog manure (LHM) application. Increasing manure rates improved grass yield across all sites the first growing season after treatment, from 1626 to 3576 kg ha-1. Although absolute increases in production were greatest on tame pasture, relative yield increases were similar among sites. Average crude protein (CP) concentration also increased from 69 to 91 g kg-1 in the first year. Despite low rainfall and the absence of a yield response in the second year, grass CP and crude protein yield (CPY) were maximized with increased manure application, highlighting the positive effects of manure on forage production, even with drought. Forb yields demonstrated variable effects among sites, with increasing manure decreasing alfalfa and increasing native forbs. Overall, both semi-arid tame pastures and native rangelands responded positively to LHM application, highlighting the complementary nature of hog and forage production under these conditions. Key words: Crude protein yield, forage, hog manure, injection, native rangeland, precipitation
CDC Golden field pea
Authors: Warkentin Tom , Vandenberg Albert , Banniza Sabine , Slinkard Al
Published: April 2011

CDC Golden, a yellow cotyledon field pea (Pisum sativum L.) cultivar, was released in 2003 by the Crop Development Centre, University of Saskatchewan for distribution to Select seed growers in Saskatchewan and Alberta through the Variety Release Committee of the Saskatchewan Pulse Growers. CDC Golden has a semileafless leaf type, good lodging resistance, medium-sized, round seeds, and good yielding ability. CDC Golden is adapted to the field-pea-growing region of western Canada. Key words: Field pea, Pisum sativum L., cultivar description
Evaluating the performance of alfalfa cultivars in rotationally grazed pastures
Authors: Papadopoulos Y. A. , McKenzie D. B. , McRae K. B. , Clark E. A. , Charmley E.
Published: April 2011

Although alfalfa (Medicago sativa L.) is an important and reliable hay crop in eastern Canada, it is generally not considered suitable for pastures. However, local studies have shown that alfalfa is capable of superior yield in mixtures under rotational grazing. This study evaluates the performance of commercially available, locally adapted, hay-type alfalfa cultivars and new experimental, grazing-type alfalfa synthetics under hay and two rotationally grazed regimes. Ten alfalfa cultivars, including five hay-type and five grazing-type cultivars, were seeded with the timothy (Phleum pratense L.) cultivar, Richmond, in mixtures. The two pasture regimes consisted of grazing to low and high residual heights. Over two dry growing seasons, the pasture management with high residual grazing height was more productive than the low; on average lenient rotational grazing pressure (high residual heights) produced 20% higher yield than low residual heights. Alfalfa cultivars selected specifically for continuous grazing were not, on average, superior to those hay-type cultivars selected for general adaptability to soil and environmental conditions in Atlantic Canada. Differences among cultivars within alfalfa type were significant. Over 2 production years, mixtures containing the hay-type cultivar, Apica, and the grazing type, Alfagraze, produced more dry matter on average than three others in the study, regardless of management regime. Key words: Grazing height, cattle grazing
Swath grazing potential of spring cereals, field pea and mixtures with other species
Authors: Vern S. Baron Arvid Aasen, , Clayton George W. , Campbell Dick A. , McCartney Duane H.
Published: April 2011

There is little information on the relative suitability of cereal species and field pea or their mixtures for winter swath grazing. The objective of this study was to compare the swath grazing potential of small-grain cereal and field pea (Pisum sativa L.) monocultures, their mixtures, and mixtures with other species, by evaluating forage yield in the fall and changes in nutritive value due to weathering from fall until spring. The monocultures and mixtures were seeded in early summer and swathed in late September with conventional farm equipment for 3 yr. Dry matter yield was measured by harvesting a subplot (1.22 × 3.62 m) across each plot prior to swathing. A cross-section sample of swath was taken for quality determination immediately after swathing, in late November and April. In vitro digestible organic matter (IVDOM), protein, and neutral (NDF) and acid detergent fiber (ADF) concentrations were measured for each sampling time. Generally, barley (Hordeum vulgare L.), oat (Avena sativa L.) and field pea monocrops produced similar yields, and mixtures did not out-yield monocrops. Yield of the barley/oat mixture was more stable from year to year than the respective monocrops. Addition of field pea to cereals in mixtures increased crude protein slightly and reduced NDF over cereal monocrops, but field pea mixtures did not improve nutritive value compared with the field pea monocrop. In one year with severe weathering conditions, field pea and field pea mixtures lost nutritive value faster than cereal monocrops initially, but had nutritive value similar to the cereal monocrops by April. Mixtures and monocrops lost nutritive value at a similar rate due to weathering. Added costs of growing mixtures rather than monocrops were not offset by superior yield, nutritive value, or resistance to weathering. Key words: Winter swath grazing, cereal and field pea mixtures, weathering, nutritive value
Theoretical hybridization potential of transgenic safflower (Carthamus tinctorius L.) with weedy relatives in the New World
Authors: McPherson Marc A. , Good Allen G. , Keith C. Topinka A. , Hall Linda M.
Published: April 2011

Carthamus tinctorius L. (safflower) is being evaluated as a crop for the production of plant-made pharmaceuticals using an oleosin fusion protein system. We evaluated the potential for transgenic gene flow from C. tinctorius to wild or weedy relatives in western Canada. Cytogenetic and phylogenetic studies with most of the species of Carthamus have demonstrated that cultivated C. tinctorius has the ability to hybridize with at least six wild or weedy relatives worldwide. Of the four naturalized wild relatives in the New World, only two, C. oxyacanthus and C. creticus, have successfully been crossed with C. tinctorius to produce fertile hybrids. Data from artificial crosses resulting in fertile offspring indicate the biological potential of a hybridization event, but only if the species are temporally and spatially sympatric can this occur. Based on the New World distribution of C. oxyacanthus and C. creticus we predict that hybridization with transgenic C. tinctorius could occur in some areas of Argentina, Chile and localities within several states in the United States including California, Florida, Illinois, Kansas, New Mexico, Ohio, Oklahoma, Oregon, Utah, and Texas. Locations in the New World where wild species of Carthamus have not been naturalized may provide biologically isolated locations for the cultivation of a transgenic safflower crop. Key words: Carthamus, safflower, transgenic, hybrid, gene flow, introgression.
Tillage or no-tillage: Impact on mycorrhizae
Authors: Kabir Zahangir
Published: April 2011

Arbuscular mycorrhizal (AM) fungi are ubiquitous in agricultural soils. These fungi play important roles in plant nutrition and soil conservation. The persistence of AM fungi in ecosystems depends on the formation and survival of propagules (e.g., spore, hyphae and colonized roots). While spores are considered to be resistant structure that may be view as “long-term” propagules when viable host plants are not present, hyphae are considered to be the main source of inocula when host plants are present and the soil is not disturbed. Tillage is an integral part of modern agriculture that can modify the physical, chemical and biological properties of a soil. Consequently, tillage practices may also affect AM fungi. The various tillage practices used in the management of soil for maximum crop production may negatively impact the survival of AM fungal propagules. In tilled soil, certain AM species may survive while others may disappear. Because AM fungi are more abundant in the topsoil, deep plowing may dilute their propagules in a greater volume of soil, thereby reducing the level of infection of a plant root. Tillage is particularly detrimental to AM hyphae if the soil is tilled in the fall and the hyphae are detached from the host plant. Under no-till (NT), AM fungi survive better, particularly when they are close to the host crop on which they developed. There is speculation that in NT systems, plants may follow old root channels and potentially encounter more AM fungal propagules than plants growing in soil that has been tilled. Management of AM fungi in NT soil is essential to maximizing benefits to crops. This review reports how tillage practices affect AM fungi species richness, survivability and infectivity, and how conservation tillage can increase AM fungi survival, consequently improving plant phosphorus uptake and soil aggregate stability. Key words: Arbuscular mycorrhizal fungi, conservation tillage, conventional tillage, P uptake, soil aggregate stability, cover crops, crop yield
Daylength affects both free and conjugated indole-3-acetic acid levels in leaves and flowering in Doritis pulcherrima (orchid)
Authors: Wen-Shaw Chen Chiung-Kuei Huang, , Chen Yun-An
Published: April 2011

Total indole-3-acetic acid (IAA) levels (free IAA plus IAA conjugates) in Doritis pulcherrima (Doritis pulcherrima Lindley, cv. S 84-335-2) leaves were threefold lower in plants exposed to 30 d of short-day (SD) conditions than in plants exposed to 30 d of long-day (LD) conditions. Free IAA levels were also significantly lower in SD-treated leaves than those in 0 day of photoperiodic treatment and 30 d of LD. Results indicate that plants exposed to 30 d of SD contained significantly higher levels of ester-IAA and reduced amide-IAA concentrations compared to those grown under LD conditions. A high level of ester-IAA and a reduction of amide-IAA in leaves may be related to increased SD floral initiation ability in D. pulcherrima. Key words: Doritis pulcherrima, floral initiation, indole-3-acetic acid, photoperiod
Effect of tillage system and crop sequence on irrigated sugarbeet production
Authors: Moyer J. R. , Nitschelm J. , Regitnig P. , Blackshaw R. E. , Huang H. C. , Chang C.
Published: April 2011

Sugarbeets (Beta vulgaris L.) are grown on intensively tilled-irrigated land in southern Alberta, which is subject to soil erosion by wind. Experiments were conducted on commercial fields near Burdett, AB, to determine the effect of the tillage system and previous crops on sugarbeet production. The previous crops were dry bean (Phaseolus vulgaris L.) or wheat (Triticum aestivium L.) and the tillage systems were conventional (moldboard plow, vibrashank cultivator, harrow, packer), minimum (double disc, self-cleaning harrow, glyphosate) or no tillage (glyphosate). After dry beans, sugarbeet fresh weight and extractable sugar yields were similar with all tillage systems. All of the tillage systems left less than 100 g m-2 of plant residue on the soil surface in the spring following dry beans, which is insufficient to protect the soil from wind erosion. After wheat, sugarbeet yields were similar with minimum and conventional tillage but lower with no tillage. Both minimum and no-tillage systems left sufficient plant residue on the soil surface to protect the soil from erosion (> 200 g m-2). Sugarbeet stand density following wheat was lower with no tillage than conventional or minimum tillage, reflecting poor seed placement and daily maximum soil temperature (5 cm depth) of up to 10°C lower under no tillage than conventional tillage. After wheat, there was a trend toward lower densities of hard-seeded annuals, such as redroot pigweed (Amaranthus retroflexus L.), after no tillage than conventional tillage. Of the cropping systems tested in this study, only the minimum tillage system after wheat provided optimum sugarbeet yield and left enough plant residue to protect the soil from wind erosion. Key words: Crop rotation, bean, wheat, sugarbeet, no-tillage
Does pollen abortion increase with plant age?
Authors: Bhattacharya Ashoke
Published: April 2011

The large tropical forest tree, Anacardium excelsum (Bertero & Balb. Ex Kunth) Skeels, of the family Anacardiaceae, was studied in Panama. Using Alexander’s stain, which differentiates aborted and non-aborted pollen, the proportion of aborted pollen versus plant age, size variation in aborted and non-aborted pollen and pollen:ovule ratio were estimated. Aborted pollen was smaller than non-aborted pollen regardless of plant age. The proportion of aborted pollen varied from 15.8 to 54.7% showing a steady increase with plant age, and the pollen:ovule ratio also increased with age. These results support the qualitative prediction that pollen abortion gradually increases with ageing reflecting an increase in genetic load with age. Key words: Age effect, reproductive success, tropical forest
Lovitt hard red spring wheat
Authors: DePauw R. M. , Knox R. E. , Clarke J. M. , McCaig T. N. , Clarke F. R. , Fernandez M. R.
Published: April 2011

Lovitt hard red spring wheat (Triticum aestivum L.) is adapted to the Canadian prairies. Lovitt is earlier maturing than AC Barrie with similar grain yield and smaller kernels. Lovitt has resistance to prevalent races of leaf and stem rust and loose smut. Lovitt has very good pre-harvest sprouting resistance similar to RL4137. Lovitt is eligible for grades of the Canada Western Red Spring wheat class. Key words: Triticum aestivum L., cultivar description, resistance to leaf and stem rust, dormancy
Alfalfa resistance to post-harvest Aspergillus species: Combining ability analyses
Authors: Kimbeng C. A. , Smith Jr. S. R. , Babij V. , Wittenberg K. M.
Published: April 2011

Hay making is still the most widespread technique of forage preservation. Saprophytic fungi, such as Aspergillus repens, can reduce forage quality during the post-harvest period by causing hay molding. Methods to control molding have yielded variable results, but genetic resistance has yet to be exploited. The objective of this study was to determine the mode of inheritance of resistance to post-harvest fungal growth in alfalfa. Seven parental genotypes representing a range of resistance to fungal growth (A. repens) were crossed in a complete diallel including reciprocals for a total of 42 crosses. Parental genotypes along with their progeny were screened for resistance to A. repens. The relative importance of general combining ability (GCA) and specific combining ability (SCA) effects in controlling resistance to post-harvest A. repens was compared. The results revealed a preponderance of GCA effects. The parent that supported the least amount of fungal growth produced progeny with the least amount of fungal coverage. The reverse was true for the more susceptible parents. The results indicate that breeding procedures that maximize additive gene effects, such as recurrent selection, could be effective in improving resistance to post-harvest fungal growth in alfalfa. Key words: Alfalfa, breeding, combining ability, resistance, Aspergillis repens, post-harvest fungi
ARC Sentinel spike trisetum
Authors: Woosaree J. , Acharya S. N. , Darroch B. A.
Published: April 2011

ARC Sentinel spike trisetum (Trisetum spicatum L.) Richt. (Moss 1992) is a low-growing native grass cultivar developed by the Alberta Research Council Inc. for reclamation and revegetation of disturbed sites at high elevations in the Rocky Mountains of Alberta. This is the first spike trisetum cultivar released in Canada for commercial production. This cultivar is well adapted to grow and produce viable seed during the short growing seasons found in the alpine and sub-alpine regions of the Canadian Rocky Mountains. Field observations indicate that ARC Sentinel spike trisetum can tolerate drought and winter conditions of the Canadian prairies where it is grown for seed production. Key words: Spike trisetum, Trisetum spicatum, reclamation, revegetation, cultivar description, native rasses
Nursery crop response to substrates amended with raw paper mill sludge, composted paper mill sludge and composted municipal waste
Authors: Chong Calvin , Purvis Peter
Published: April 2011

Silverleaf dogwood (Cornus alba L. ‘Argenteo-marginata’), forsythia (Forsythia × intermedia Zab. ‘Lynwood Gold’), and weigela (Weigela florida Bunge A.DC. ‘Red Prince’) were grown in #2 (6-L) containers filled with 100% bark or bark mixed with 20, 40 or 60% by volume each of raw paper mill sludge (RB group), Bio Soil compost containing 100% paper mill sludge (BCB group), Waterdown compost containing 40% paper sludge, 40% chicken manure and 20% sawdust (WCB group), and municipal compost consisting of leaf and yard waste (MCB group). A fifth substrate group (MCH) consisted of 100% hemp chips or hemp chips mixed with the same rates of municipal compost. The containers were trickle-irrigated and fertilized with a controlled-release fertilizer. Regression analysis indicated that growth among the barkamended groups was highest for dogwood and forsythia with WCB, increasing dramatically and peaking at about the 40% rate (68 and 94 g plant-1 aboveground dry weight, respectively). Growth of these species was intermediate with MCB and BCB and least with RB, increasing to rates ≥ 50% in these groups. There was no significant response of dogwood to RB. Growth of weigela increased equally with WCB and MCB substrates up to about 40% (117 g plant-1), but was not influenced by varying rates of RB and BCB. With the hemp-amended MCH group, growth of all three species increased to rates ≥ 50% (62, 93, and 116 g plant-1 for dogwood, forsythia and weigela, respectively). Growth of the three species over most rates of all substrate groups was similar to, or exceeded that in 80% bark: 15% peat: 5% topsoil, a proven nursery mix. Aboveground dry weight of all three species was positively correlated with soluble salts concentrations in the substrates sampled at planting and on other sampling dates during the season. Key words: Nursery, ornamentals, waste and compost utilization
Leaf and stem nutritive value of timothy cultivars of different maturity at an irrigated site in southwestern Saskatchewan
Authors: Jefferson Paul G.
Published: April 2011

Leaf and stem structural components contribute to variation in nutritive value among timothy (Phleum pratense L.) cultivars. Modelling timothy growth and nutritive value requires a better understanding of this variation. A trial of 11 timothy cultivars was conducted on irrigation at Swift Current, Saskatchewan from 1995 to 1997. Leaf:stem ratio, forage yield, days to maturity, N, P, acid detergent fiber (ADF) and neutral detergent fiber (NDF) concentrations, N/P ratio and P uptake of leaf and stem components were determined for spring growth forage. Two N fertilizer rates (100 and 150 kg N ha-1) did not consistently affect leaf and stem nutritive value. Cultivars differed in maturity, stem P, stem N, stem NDF, leaf NDF and leaf ADF in all 3 yr. Days to maturity was correlated to stem P concentration (r = 0.59, P < 0.05, to 0.77, P < 0.01) and leaf ADF concentration (r = 0.59, P < 0.05, to 0.82, P < 0.01) in all 3 yr but not to stem NDF concentration. Days to maturity was correlated to stem N concentration and leaf NDF concentration in 1995 and 1997 but not in 1996. However, days to maturity did not explain the observed variation among cultivars for stem NDF concentration and several other variables. While maturity differences among timothy cultivars must be taken into account when selecting for improved nutritive value or modelling growth and quality, additional variation for these traits was evident. Key words: Forage quality, Phleum pratense L., maturity, forage yield
Is phosphorus fertilization necessary for watermelon production on high phosphorus soils?
Authors: Geleta Samuel B , Briand Christopher H , Womack Harry E , Brinsfield Russell B , Mulford F. Ron
Published: April 2011

Nutrient loading has created water quality problems in the Chesapeake Bay watershed of the United States. This study was designed to examine if a high yield of quality watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] can be produced with reduced phosphorus (P) fertilizer inputs and the use of a preceding cover crop on high P soils of the Eastern Shore of Maryland. Watermelon was planted on a Norfolk soil (fine loamy, siliceous, thermic type kandiudults) in a split plot design, with four replications. The main plot treatments were cover crops (rye versus no cover) and the sub-plot treatments were five different P-fertilizer rates ranging from 0 to 60 kg P ha-1, at 15 kg ha-1 increments. Following harvest, all P fertility regimes left behind “excessive” P levels based on soil tests. The addition of P-fertilizer to these soils was unnecessary for the production of a high yield of marketable quality watermelons. In two of three sites, the use of cover crops preceding the watermelon crop increased yields and fruit size. Use of a rye cover crop and reduced P-fertilizer inputs could have a positive environmental impact by reducing the risk of P over-loading without negatively impacting watermelon yield and quality. Key words: Watermelon quality, phosphorus-reduction, rye cover crop, phosphorus loading
Leaf removal and prohexadione-calcium can modify Camarosa strawberry nursery plant morphology for plasticulture fruit production
Authors: Reekie J. Y. , Hicklenton P. R. , Duval J. R. , Duval C. K. , Struik P. C.
Published: April 2011

Mowing and the application of a new gibberellin biosynthesis inhibitor, prohexadione-calcium (ProCa), were studied as methods to modify the bare-root transplant morphology of Camarosa strawberry (Fragaria × ananassa Duchesne) in a Nova Scotia nursery. The effect these nursery practices had on fruit production in annual hill plasticulture was also determined. In one experiment Camarosa plants were sprayed with ProCa at an active ingredient concentration of 62.5 mg L-1 on Aug. 22, Sep. 05, or Sep. 19, 2001 and 2002, corresponding, respectively, to growing degree days (10°C base) of 800, 894 and 965 in 2001 and 726, 821 and 908 in 2002. Application on Aug. 22 increased production of daughter plants, especially those of marketable size, by increasing the number of daughters per meter of runner and allocating more dry matter to marketable daughters. In a second experiment, field plots were mowed and/or treated with ProCa at an active ingredient concent ration of 62.5 mg L-1 on Sep. 05 or Sep. 19, 2001 and 2002. All plants were dug in early October, shipped to Dover, Florida, and transplanted into plasticulture for fruit production. At digging, plants that had been mowed or treated with ProCa on Sep. 05 were reduced in plant height and total leaf area compared with untreated plants. Plants that were treated both with ProCa and mowed were the shortest. Fruit yield was higher from treated than from untreated plants. In 2001, the treatments increased early fruit production. Key words: Fragaria × ananassa, mowing, gibberellin biosynthesis inhibitor, phenology, height control
Leo soybean
Authors: Poysa V. , Woodrow L. , Yu K.
Published: April 2011

Leo is a large-seeded tofu-type soybean [Glycine max (L.) Merr.] cultivar with elevated seed protein content developed at the AAFC Research Centre, Harrow, Ontario. Leo has yellow hilum and acceptable tofu processing quality for foreign and domestic markets. Key words: Glycine max (L.) Merr., soybean, cultivar description, tofu
Influence of four successive annual applications of elemental S and sulphate-S fertilizers on yield, S uptake and seed quality of canola
Authors: Malhi S. S.
Published: April 2011

The effectiveness of elemental S fertilizers in increasing crop yield in S-deficient soils depends on the rate at which S is oxidized to sulphate in soil for plant uptake. A 4-yr field experiment (1999 to 2002) was conducted with canola (Brassica napus L. or Brassica rapa L.) on a S-deficient loamy sand Gray Luvisol soil near Tisdale in northeastern Saskatchewan to determine the effectiveness of elemental S and sulphate-S fertilizers applied annually at different times and S rates on seed and straw yield, oil and protein concentration in seed, concentration and uptake of S in seed and straw, amount of residual sulphate-S in soil, and recovery of applied S in plant, soil and plant + soil. The S fertilizer treatments included granular types of two bentonite -elemental S fertilizers (ES-90 and ES-95), one sulphate-S (ammonium sulphate), one containing elemental S and sulphate-S (Agrium Plus), and a zero-S control. The S fertilizers were surface-broadcast at 10 or 20 kg S ha-1 rates in the previous autumn or in spring, and incorporated into the soil a few days prior to seeding in May. Canola plants in the zero-S control showed S deficiency in the growing season. Seed yield, straw yield, oil concentration in seed, and S concentration and uptake in seed and straw increased with the sulphate-S fertilizer in all years. There was no significant increase in seed yield from the elemental S fertilizers in 1999, though autumn application tended to give slightly greater seed yield than the spring application. Elemental S fertilizers usually increased seed yield and S uptake significantly over the zero-S control, but yield and S uptake were less than the sulphate-S fertilizer in most cases in 2000, in many cases in 2001 and in some cases in 2002, especially when the S fertilizers were applied in spring. Autumn-applied elemental S usually had greater seed yield and S uptake than the spring-applied elemental S in 2000, 2001 and 2002. On the other hand, autumn-applied ammonium sulphate produced or tended to produce lower seed yield and S uptake than spring-applied ammonium sulphate in some cases. There was little effect of S fertilizer application on protein concentration in seed. In summary, the results indicated that elemental S fertilizers were not effective in increasing canola yield and S uptake on the S-deficient soil in the first year of application. The elemental S fertilizers became effective in the second to fourth year, but seed yield and S uptake were still less than those obtained with sulphate-S fertilizer, particularly when the S fertilizers were applied in spring. The findings suggest the need for research on best management practices to improve effectiveness of elemental S fertilizers. Key words: Canola, elemental and sulphate S fertilizers, oil and protein concentration, seed yield, sulphur uptake
Influence of formulation of elemental S fertilizer on yield, quality and S uptake of canola seed
Authors: Malhi S. S. , Solberg E. D. , Nyborg M.
Published: April 2011

The rate of S oxidation in elemental S fertilizers to plant-available sulphate-S depends on factors that affect microbial activity, such as soil moisture, temperature, aeration and size of fertilizer granules. Three field experiments were conducted on S-deficient Gray and Dark Gray Luvisol soils (Typic Cryoboralf) during 2000 and 2001 in Saskatchewan (exp. 1 at Porcupine Plain and exp. 3 at Canwood) and Alberta (exp. 2 at Legal) to determine the effects of formulation of elemental S fertilizers on yield, oil, protein and S concentration, S uptake, percent recovery of applied S and N uptake in seed of canola (Brassica napus L. ‘A4573’ at Porcupine Plain and ‘Invigor 2663’ at Legal and Canwood). In exp. 1 (2000 and 2001) and exp. 2 (2000), treatments included five elemental S fertilizers (granular ES-99, ES-95, ES-90 and Biosul-90; and Biosul-50 suspension), granular potassium sulphate and zero-S control. In exp. 3, treatments included eight elemental S fertilizers (granular ES-99, ES-95, ES-90 and Biosul-90; powder Lab fine ES-99.5, ES Settle-47 and ES SPB571-85.8; and Biosul-50 suspension), 21.7% elemental S plus 18.7% sulphate-S (Agrium Plus), blend of granular ES-90 and ammonium sulphate (1:1), granular ammonium sulphate and zero-S control. The S fertilizers were surface-broadcast or sprayed at 15 and 30 kg S ha-1 rates within 2–3 d after sowing in spring. Canola plants in the zero-S treatment showed S deficiency in the growing season, and seed yield increased with sulphate-S fertilizer by 21.8, 1.4, and 3.6 times in exps. 1, 2, and 3, respectively. There was little effect of S fertilizer on protein concentration in seed. Biosul-50 suspension in all experiments and powder forms of elemental S fertilizers, used only in exp. 3, were almost as effective as sulphate-S fertilizers. In all experiments, granular elemental S fertilizers had no or only a very small effect on yield, S uptake, percent recovery of applied S, N uptake, oil concentration, S concentration and protein concentration of canola seed in the first year of application. In the second year of exp. 1, granular elemental S fertilizers tended to increase yield, S uptake, N uptake, oil concentration, and S concentration of canola seed, but none of them produced seed yield or improved other parameters of canola seed comparable with the sulphate-S and elemental S powder or suspension fertilizers. In summary, granular elemental S fertilizers were not effective in increasing canola seed yield and S uptake on S-deficient soils in the first year of application. After the second annual application, most granular elemental S fertilizers tended to correct deficiency of S in canola plants, but improvements in yield and other parameters of seed were still less than the sulphate-S and suspension or powder forms of elemental S fertilizers. Key words: Canola, elemental and sulphate S fertilizers, granular, suspension, oil and protein content, seed yield, S uptake
Economic evaluation of seeding decisions in hybrid and open-pollinated herbicide-resistant canola (Brassica napus)
Authors: Upadhyay B. M. , Smith E. G. , Clayton G. W. , Harker K. N. , O’Donovan J. T. , Blackshaw R. E.
Published: April 2011

Herbicide-resistant canola (Brassica napus) is widely cultivated in western Canada. Data from a multi-year field experiment conducted at three locations in Alberta were used to investigate the effect of canola cultivar, time of seeding, polymer seed coating (PSC) on profitability and the net return risk. Cultivars included hybrid and open pollinated. Time of seeding was early and late fall, and early and normal spring. The hybrid canola generally had higher mean net return than the open-pollinated cultivar. The probability of thin canola stand was higher for fall dormant seeding compared with spring seeding. The use of PSC for early fall dormant seeding reduced the likelihood of thin canola stand, which translated into risk-efficient decision. However, PSC use for late fall seeding had mixed results. Early and normal spring seeding was generally risk-efficient at all locations. In exceptional cases, net returns from late fall dormant seeding (with or without PSC) were similar to that of spring seeding. Re-seeding of fall seeded canola in the spring could be beneficial, if the plant density was below 20 plant m-2. Seeding decisions were robust across a wide range of canola prices, based on the probability of negative net returns. Key words: Canola, fall seeding, net returns, polymer seed coat, re-seeding, risk
Lillian hard red spring wheat
Authors: DePauw R. M. , Townley-Smith T. F. , Humphreys G. , Knox R. E. , Clarke F. R. , Clarke J. M.
Published: April 2011

Lillian, hard red spring wheat (Triticum aestivum L.), exhibited reduced cutting by the wheat stem sawfly (Cephus cinctus Nort.) and is adapted to the Canadian prairies. Lillian produced significantly more grain yield than AC Abbey and Neepawa and its grain yield and protein concentration were similar to AC Barrie. It matured significantly earlier than Superb and Laura, and had improved resistance to leaf rust and leaf spotting diseases compared to AC Abbey. Lillian is eligible for all grades of the Canada Western Red Spring (CWRS) wheat class. Key words: Triticum aestivum L., cultivar description, grain yield and protein, resistance wheat stem sawfly, leaf and stem rust
Fertilization, seeding date, and seeding rate for malting barley yield and quality in southern Alberta
Authors: McKenzie R. H. , Middleton A. B. , Bremer E.
Published: April 2011

Weather conditions are often unfavourable for malting barley quality in southern Alberta, but agronomic practice may improve the probability of attaining acceptable quality. The objective of this study was to determine optimum agronomic practice (cultivar, fertilization, seeding date and seeding rate) for yield and quality of malting barley in southern Alberta. Field trials were conducted at 12 dryland sites and 2 irrigated sites over a 3-yr period (2001–2003). At each site, five experiments were conducted with the following treatments: (1) N rate (0, 40, 80, 120, and 160 kg N ha-1), (2) P rate (0, 6.5, 13 and 19.5 kg P ha-1), (3) K rate (0, 25 and 50 kg K ha-1), (4) S rate (0, 10, and 20 kg S ha-1), and (5) seeding date (three dates at 10-d intervals) and seeding rate (150, 200, 250, 300, and 350 viable seeds m-1). Seven cultivars were included in the first experiment and two cultivars were included in the remainder of the experiments. Maximum grain yields were achieved when fertilizer + available soil N (estimated from unfertilized grain N yield) exceeded 31 kg N Mg-1 maximum grain yield, whereas protein concentrations were usually acceptable if fertilizer + available soil N was between 25 and 40 kg N Mg-1 maximum grain yield. Higher N rates generally reduced kernel size. Cultivar differences in N response were negligible. Application of P, K, or S did not affect malt yield or quality. Seeding delays of ≈ 20 d reduced grain yields by an average of 20%, with relatively greater yield declines under drought stressed conditions. Delayed seeding did not affect or slightly increased grain protein concentration. Kernel size was both increased and decreased by delayed seeding. Increased seeding rates from 150 to 350 viable seeds m-2 generally provided small yield gains, slight reductions in grain protein concentration and reduced kernel size. The most beneficial agronomic practices for malt barley production in southern Alberta were early seeding and application of N fertilizer at rates appropriate to the expected availability of moisture and soil N. Key words: Hordeum vulgare, nitrogen fertilizer, phosphorus, potassium, sulphur, protein, plump kernels