bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing fruit cultivars for organic production systems: A review with examples from apple and strawberry
Authors: Jamieson A. R.
Published: April 2011

The amount of fruit and vegetables produced under organic production systems, irrespective of how “organic” is delimited, has been steadily increasing. Organic production is largely based on cultivars that were originally developed for conventional production systems. The prospects of breeding specifically for organic systems are intriguing. One approach is identifying the major constraints with which organic growers must contend (often diseases or insect pests) and then incorporating stable genetic resistance. A more complex approach is to define an organic crop ideotype and derive an index of traits as a selection criterion. How effective are these methods expected to be for improving clonally-propagated fruit crops? In addition to the importance of the breeding goals, the technologies employed are also of concern. The topic will be examined with special reference to breeding strawberries and apples. Key words: Fruit breeding, strawberry (Fragaria × ananassa Duch.), apple (Malus × domestica Borkh.), disease resistance, selection environment
Plant species diversity, ecosystem function, and pasture Management—A perspective
Authors: Sanderson M. A. , Goslee S. C. , Soder K. J. , Skinner R. H. , Tracy B. F. , Deak A.
Published: April 2011

Grassland farmers face many challenges in pasture management including improving sustainability, reducing inputs of fertilizers and pesticides, and protecting soil resources. In this paper we provide our perspective on managing plant diversity within and among pastures as one tool to aid producers in meeting these challenges. Pasture ecosystems can be highly diverse, with a complex array of organisms contributing to ecosystem functioning. Within the broad range of plant and animal biodiversity in pastures, plant species diversity may be the most amenable to manipulation or management. Reported benefits of plant diversity in grasslands include: increased forage production, greater ecosystem stability in response to disturbance, and reduced invasion by exotic species such as weeds. Some view diversity as a sort of insurance policy where different species contribute in their own time or can take the place of species that fail from stress or mismanagement. Using mixtures of several forages in pastures, in some instances, can improve forage yield and reduce weed invasions. Pasture management for increased plant species diversity, however, is not simply mixing and planting as many forage species as possible. The kinds and amounts of different forage species along with their arrangement within and among pastures at the farm scale are critical features that must be considered. Tools must be developed to determine the appropriate species mixtures for varying soils, landscapes, climate and purposes to fulfill multiple functions for producers. Key words: Grazing ecosystem; forages; diversity; ecosystem function; ecosystem services
Switchgrass as a biofuels feedstock in the USA
Authors: Sanderson M. A. , Adler P. R. , Boateng A. A. , Casler M. D. , Sarath G.
Published: April 2011

Switchgrass (Panicum virgatum L.) has been identified as a model herbaceous energy crop for the USA. In this review, we selectively highlight current USDA-ARS research on switchgrass for biomass energy. Intensive research on switchgrass as a biomass feedstock in the 1990s greatly improved our understanding of the adaptation of switchgrass cultivars, production practices, and environmental benefits. Several constraints still remain in terms of economic production of switchgrass for biomass feedstock including reliable establishment practices to ensure productive stands in the seeding year, efficient use of fertilizers, and more efficient methods to convert lignocellulose to biofuels. Overcoming the biological constraints will require genetic enhancement, molecular biology, and plant breeding efforts to improve switchgrass cultivars. New genomic resources will aid in developing molecular markers, and should allow for marker-assisted selection of improved germplasm. Research is also needed on profitable management practices for switchgrass production appropriate to specific agro-ecoregions and breakthroughs in conversion methodology. Current higher costs of biofuels compared to fossil fuels may be offset by accurately valuing environmental benefits associated with perennial grasses such as reduced runoff and erosion and associated reduced losses of soil nutrients and organic matter, increased incorporation of soil carbon and reduced use of agricultural chemicals. Use of warm-season perennial grasses in bioenergy cropping systems may also mitigate increases in atmospheric CO2. A critical need is teams of scientists, extension staff, and producer-cooperators in key agro-ecoregions to develop profitable management practices for the production of biomass feedstocks appropriate to those agro-ecoregions. Key words: Bioenergy, biomass conversion technologies, Panicum virgatum L., stand establishment, switchgrass improvement, USDA-ARS
Differential response of weed and crop species to potassium and sulphur fertilizers
Authors: Grant C. A. , Derksen D. A. , Blackshaw R. E. , Entz T. , Janzen H. H.
Published: April 2011

Fertilization may affect the relative competitive ability of weeds and crops if the growth response to fertilizer differs among species. Greenhouse studies were conducted to evaluate the relative biomass yield response of 19 weed species and the crops canola (Brassica napus L.) and spring wheat (Triticum aestivum L.) to potassium (K) and sulphur (S) fertilization. Seven weed species showed a significant increase in biomass production at 6 wk with K fertilization, but biomass production of canola and wheat did not increase with K addition. Sulphur fertilizer increased the biomass production of canola, flixweed (Descurainia sophia L.) and wild mustard (Sinapis arvensis L.), three of the four Cruciferae species evaluated, as well as that of hairy nightshade (Solanum sarrachoides Sendtner), round-leaved mallow (Malva pusilla Sm.) and stork’s-bill [Erodium cirutarium (L.) L’Her. Ex. Ait.]. Sulphur fertilizer did not increase the biomass production of spring wheat or of any grass weed species. The data from the greenhouse study support the concept that fertilization may shift the relative competition between a crop and the weed population if the weeds are more responsive than the crop to the type of fertilizer applied. However, this concept should be tested under field conditions. Key words: Integrated weed management, sulphur, potassium
Vesicular arbuscular mycorrhizae-mediated uptake and translocation of P and Zn by wheat in a calcareous soil
Authors: Goh Tee Boon , Banerjee M. R. , Tu Shihua , Burton D. L.
Published: April 2011

Vesicular-arbuscular mycorrhizae (VAM) have been credited with improving the growth and mineral nutrition of many host plants but these effects are moderated by soil factors and nutrient balance. We investigated the combined effects of VAM, zinc and phosphorus application on the growth, uptake and translocation of nutrients in wheat using a calcareous soil marginal in P and Zn. Wheat was grown in a growth chamber under various combinations of VAM, P and Zn with measurements done at heading stage and maturity. Vegetative dry matter accumulation was increased by P additions and reduced by VAM infection. Both P addition and VAM infection increased grain yield. Zinc concentration and uptake were generally reduced by P additions and VAM infection. There was an absence of antagonistic effects of Zn additions on P concentration and uptake. In contrast, VAM infection had both positive and negative effects on P uptake depending on the growth stage and translocation of nutrients. We observed that in calcareous soils where the Zn and P fertilizer combinations were adequate for growth, the role of VAM in enhancing the translocation of Zn and P from root and straw to grain is beneficial towards seed set and yield. Key words: VA mycorrhizae, P and Zn fertilization, calcareous soil, wheat, yield, nutrient acquisition, translocation
Grain yields from spring-sown Canadian wheats grown in saline rooting media
Authors: Steppuhn H. , Wall K. G.
Published: April 2011

Farmers seek information about the salt tolerances of wheat. Two greenhouse tests conducted at the Swift Current Salt Tolerance Testing Laboratory determined the response of four spring-sown Canadian wheat cultivars (Katepwa, Biggar, Fielder and Kyle) to increasingly saline rooting media. The first test followed the United States Salinity Laboratory procedure of increasing root-zone salinity gradually after plant emergence, and the second provided full complements of salts before seeding. The plants were grown in sand tanks irrigated four times daily with hydroponic solutions containing salt concentrations of up to 14 dS m−1 equivalent electrical conductivity for saturated soil paste extracts (ECe) Grain yield and plant height began to decline within all cultivars at equivalent ECe-values ranging between 0.5 and 2.5 dS m−1. At 4 dS m−1, grain production dropped to 80% or less of that produced in non-saline rooting media. Kyle and Fielder plants showed slightly more salt tolerance than those of Katepwa or Biggar (i.e., moderately sensitive rather than sensitive). Gradually adding the salts after plant emergence resulted in a tendency for greater salt-tolerance estimates than obtained by subjecting the plants to the full complement of salts at seeding. At the concentrations tested, the salinity affected the number of fertile spikes per plant more than it affected the number of plants reaching harvest. Key words: Salt tolerance, salt resistance, salinity, crop growth modelling, crop response
OAC Elmira winter barley
Authors: Falk D. E. , Reinbergs E. , Meatherall G.
Published: April 2011

OAC Elmira is a high-yielding, disease-resistant, hardy winter barley adapted to Southern Ontario. OAC Elmira has good winter hardiness and high hectoliter weight. It has better disease resistance than any of the check cultivars and long straw with a lax, nodding head. It was developed by the Ontario Ministry of Agriculture and Food through the Crop Science Department of the University of Guelph. Key words: Hordeum vulgare L., high yield, disease resistance, winter hardiness
Total, water-soluble and acid-soluble arabinoxylans in western Canadian barleys
Authors: Fleury M. D. , Edney M. J. , Campbell L. D. , Crow G. H.
Published: April 2011

Non-starch polysaccharides, such as β-glucan and arabinoxylan, are often implicated as a cause of the poor feeding value of barley for poultry. Levels of arabinoxylan in Canadian barley types, though, have not been thoroughly investigated. Total, water-extract and acid-extract arabinoxylan levels were determined for six-rowed (covered), two-rowed (covered) and hulless (both six- and two-rowed) barley (Hordeum vulgare) cultivars and genotypes grown in the 1991 Western Canadian Barley Cooperative Program. Analyses were performed using a dichromatic modification of the orcinol method. The six-rowed barley types contained significantly greater total, water-extract and acid-extract arabinoxylan concentrations than hulless or two-rowed types (P < 0.05). In hulless barley, total (P < 0.01), water-extract (P < 0.01), and acid-extract (P < 0.05) levels of arabinoxylan were, respectively, less than, greater than and similar to levels of arabinoxylan in samples of two-rowed barley. Environment had a significant effect on levels of water-extract (P < 0.01) and acid-extract (P < 0.05) arabinoxylan. Genetic differences affected the arabinoxylan content of cultivars and genotypes within each of the barley types (P < 0.05). Levels of acid-extract arabinoxylan were positively correlated with the viscosities of acid extracts of the barleys (P < 0.001). Key words: Arabinoxylan, barley, viscosity, acid-extract, pentosans
AC Colibri soybean
Authors: Voldeng H. D. , Frégeau-Reid J. A. , Guillemette R. J. D. , Leonard D. A. , Cober E. R.
Published: April 2011

AC Colibri is a 2500 heat unit soybean (Glycine max [L.] Merr.) cultivar developed for natto soyfood production. Key words: Soybean, cultivar description, natto
Micron soybean
Authors: Voldeng H. D. , Frégeau-Reid J. A. , Guillemette R. J. D. , Leonard D. A. , Cober E. R.
Published: April 2011

Micron is a 2600 heat unit soybean (Glycine max [L.] Merr.) cultivar developed for natto soyfood production. Key words: Soybean, cultivar description, natto
AC Cheng flue-cured tobacco
Authors: Brandle J. E. , Ankersmit J. C. D. , Rogers W. D.
Published: April 2011

AC Cheng is a flue-cured tobacco (Nicotiana tabacum) cultivar bred at the Pest Management Research Centre of Agriculture and Agri-Food Canada. It is a cultivar with high leaf quality and resulted from crosses between flue-cured cultivars and breeding lines, and Nicotiana rustica (+) Nicotiana tabacum somatic hybrids (somatic 9/77CD15//2*Delgold) (Douglas et al. 1981). AC Cheng is adapted to the tobacco growing areas of Ontario. Key words: Nicotiana tabacum, somatic hybrid
Effect of soil temperature, seeding depth and cultivar on wheat tolerance to simulated ethalfluralin carryover
Authors: Darwent A. L. , Lefkovitch L. P. , Mills P. F.
Published: April 2011

Field and controlled environment experiments were conducted at Beaverlodge, Alberta to determine the effect of soil temperature, seeding depth and cultivar on wheat (Triticum aestivum L.) tolerance to ethalfluralin. In one experiment, ethalfluralin was applied and incorporated, and wheat was seeded at several depths in late April/early May when soil temperatures were lowest or in late May when soil temperatures had increased. Mean 3-yr wheat yields decreased by 45% as the rate of ethalfluralin increased from 0 to 0.75 kg ha−1 and by 21% as the depth of seeding increased from 4 to 12.5 cm but the effect of ethalfluralin on yields was similar regardless of the soil temperature (time of seeding). Mean plant density decreased by 55% as the rate of ethalfluralin increased and by 25% as the depth of seeding increased. Reductions in mean plant density from ethalfluralin were slightly greater when seeded into the warmer soils. In another experiment, the effect of ethalfluralin on the yields of three wheat cultivars, Laura, Conway and Biggar was similar, i.e. the cultivar × rate of ethalfluralin interaction was not significant. However, the mean plant density of Biggar, averaged over rates of ethalfluralin, was less than that of the other cultivars in 1 of 2 yr. In a controlled environment experiment, the oven-dry weight and percent emergence of wheat shoots of the cultivars, Katepwa, Laura and Conway, seeded at 1.5 or 4 cm into soils containing ethalfluralin at concentrations of 0 to 4 ppm and maintained at temperatures of 4.5 or 15 °C, were reduced by decreases in temperature and increases in the rate of herbicide and depth of seeding. However, the interaction of soil temperature × rate of ethalfluralin was not significant for the oven-dry weight of the wheat shoots and the reduction in percent emergence of the wheat shoots as the rate of ethalfluralin increased was only slightly greater at 4.5 °C than at 15 °C. These results indicate that soil temperature and cultivar selection have a minor effect on wheat tolerance to ethalfluralin while herbicide concentration and depth of seeding have a major impact. Key words: Ethalfluralin, wheat, seeding depth, soil temperature, cultivar
AC Cormoran soybean
Authors: Voldeng H. D. , Guillemette R. J. D. , Leonard D. A. , Cober E. R.
Published: April 2011

AC Cormoran is a 2600 crop heat unit soybean (Glycine max [L.] Merr.) cultivar with good yield potential. AC Cormoran has a tall determinate phenotype. Key words: Soybean, cultivar description
The inheritance of erucic acid content in Ethiopian mustard
Authors: Getinet A. , Rakow G. , Raney J. P. , Downey R. K.
Published: April 2011

Ethiopian mustard (Brassica carinata A. Braun) is a highly productive oilseed crop in the central highlands of Ethiopia. Cultivars currently in production in Ethiopia produce seed which contains 35–40% erucic acid in its oil which is undesirable for human consumption. Zero erucic acid B. carinata has recently been developed. The objective of this study was to investigate the inheritance of erucic acid in progeny of crosses between the high erucic acid cultivars Dodolla and S-67 with the zero erucic acid line C90-14. The erucic acid content of F1 seed born on either the high or low erucic acid parents was intermediate between the parents indicating embryonic control of erucic acid content in B. carinata. Erucic acid contents of backcross seed derived from the backcross to the zero erucic acid parent segregated into three classes with <0.5%, 6–16% and >16% erucic acid at a ratio of 1:2:1 and F2 seed segregated into five classes with a ratio of 1:4:6:4:1. These segregation patterns indicated that erucic acid in B. carinata was controlled by two genes acting in an additive manner with each locus contributing about 10% erucic acid. It was concluded that the B and C genomes of B. carinata each carry one gene for erucic acid synthesis. The knowledge of the inheritance of erucic acid in B. carinata will assist in the development of zero erucic acid B. carinata cultivars. Key words:Brassica carinata, erucic acid, inheritance
Leaf and stem nutritive value of timothy cultivars differing in maturity
Authors: Bélanger G. , McQueen R. E.
Published: April 2011

The nutritive value of herbage is a function of the nutritive value of its component leaves and stems and their proportion in the herbage. A previous study indicated that the proportion of leaves in the herbage did not explain entirely the differences in in vitro true digestibility and NDF concentrations between early and late-maturing timothy (Phleum pratense L.) cultivars. It was therefore hypothesized that the leaves and stems of early and late-maturing cultivars differ in nutritive value. The evolution of leaf and stem nutritive value of field-grown timothy cultivars differing in maturity, and the relationships between parameters of leaf and stem nutritive value, and the leaf to weight ratio (LWR) were studied during primary growth in two experiments. On a given date, stems of early-maturing cultivars had in vitro true digestibilities of dry matter and cell wall up to 61 g kg−1 DM and 71 g kg−1 DM lower that those of late-maturing cultivars, respectively. The NDF concentration of stems of early-maturing cultivars was up to 32 g kg−1 DM greater than that of late-maturing cultivars. There were no cultivar differences in leaf in vitro true digestibilities of dry matter and cell wall, and NDF concentration on a given date. At a given LWR, however, the leaves and stems of early-maturing cultivars had greater in vitro true digestibilities of dry matter and cell wall, and a lower NDF concentration than those of late-maturing cultivars. Our results indicate that differences in herbage nutritive value at a given stage of maturity between early- and late-maturing timothy cultivars is explained by a greater nutritive value of leaves and stems of the early-maturing cultivars. Key words: Phleum pratense L., timothy, cultivar, digestibility, cell wall, leaf, stem
The effect of temperature and photoperiod on primary floral induction in three lines of alpine bluegrass
Authors: Pahl Michelle , Darroch Barb
Published: April 2011

The effects of temperature and photoperiod on primary floral induction in three lines of alpine bluegrass (Poa alpina L.) were studied in controlled environments. These lines were developed at the Alberta Environmental Centre from single plant accessions collected from the Alberta Rocky Mountains. Plants representing all three lines were subjected to temperatures of 3, 9, and 12 °C under dark (0 h), short-day (8 h), and long-day (18 h) photoperiods for durations of 6, 10, and 14 wk. Plants were subsequently transferred to conditions of 22 °C/15 °C, 18 h photoperiod and heading response was recorded. Primary floral induction was found to be favoured by low temperatures and/or short days with marked inhibition at 12 °C. Complete dark conditions were not inductive. Six weeks of primary induction was suboptimal with only 15% of plants flowering. However, 100% of plants flowered after 10 wk of primary induction at 3 °C under both long-day and short-day conditions. Differences among lines were significant for number of heading plants, number of heads per plant, time to heading, and critical induction duration. Primary induction in line 907 occurred at longer photoperiods, warmer temperatures, and in shorter durations than the other lines indicating a lesser induction requirement. Possible implications are discussed in the use of alpine bluegrass populations for revegetating disturbed mountain sites. Key words: Floral induction, temperature, photoperiod, Poa alpina, alpine bluegrass
Sward age and weather effects on alfalfa yield at a semi-arid location in southwestern Saskatchewan
Authors: Jefferson P. G. , Cutforth H. W.
Published: April 2011

Alfalfa (Medicago sativa L.) yield in the first and second years after establishment is typically much greater than yield in subsequent years under dryland production systems in semiarid regions. Alfalfa is a deep-rooted perennial that uses soil water stored at soil depths below the reach of shallow-rooted cereals and grasses. Since alfalfa yield is positively related to evapotranspiration, this study was conducted to determine the relationship between historical alfalfa yield data and weather variables as affected by sward age. Rambler alfalfa yields collated by sward age during cultivar yield trials from 1951 to 1994 at Swift Current, Saskatchewan, were statistically related to monthly precipitation (April to August) and monthly pan evaporation (May to September) during the growing season, and to the fall and winter total precipitation (September to March). One-year-old swards yielded more than 3-, 4- or 5-yr-old swards. For 1- and 2-yr-old alfalfa swards, weather accounted for 50% and 47% of the yield variability, respectively. However, weather accounted for 85, 87 and 96%, respectively, for 3-, 4- and 5-yr-old swards. We hypothesize that soil water stored deep in the profile accounted for much of the remaining yield variability in one and two year old swards. Researchers must measure soil water use from soil depths to at least 3 m when assessing dryland alfalfa yields. Key words: Medicago sativa L., weather, modelling, forage yield
Winter hardiness and artificial frost tolerance of white clover ecotypes and selected breeding lines
Authors: Caradus J. R. , Christie B. R.
Published: April 2011

A series of experiments on white clover (Trifolium repens L.) was conducted: (1) to field test white clover frost tolerant selections in a region subjected to freezing stress, and (2) to evaluate and characterize, both in the field and in an artificial frosting environment, a number of white clover ecotypes from eastern Canada. Within the lines produced from genotypes selected for frost tolerance, there was considerable variation in the field for tolerance to winter freezing based on both vigor and winter survival. However, some of the selections were very tolerant of the conditions, with more than 90% survival after two Canadian winters. The ecotypes collected from eastern Canada were essentially acyanogenic with a small to medium leaf size. Their winter survival in the field was also variable ranging from 0 to 95% in one trial and from 0 to 85% in another. However, survival of ecotypes was correlated between two field trials (r = +0.45, P < 0.05). Artificial frosting damage was correlated with second year spring vigor (r = 0.69, P < 0.001), but not consistently with winter survival. Ecotypes collected from cold regions were variable for both field and artificial frosting tolerance, but included germplasm that could be used in breeding programs seeking improved frost tolerance. Selection in artificial frosting environments can produce germplasm that is tolerant of winter freezing stress in the field. Key words: White clover, frost tolerance, winterhardiness, Trifolium repens, selection, ecotypes
Effects of timings of inoculation with Mycosphaerella pinodes on yield and seed infection of field pea
Authors: Xue A. G. , Warkentin T. D. , Kenaschuk E. O.
Published: April 2011

Inoculated field experiments were carried out in 1994 and 1995 to study the effect of the timing of inoculation with Mycosphaerella pinodes (Berk. & Bloxam) Vestergren on disease development, yield reduction and seed infection, in three field pea (Pisum sativum L.) cv. Bohatyr, cv. Scorpio and cv. Triumph. The greatest impact of inoculation on all disease and yield parameters was at the 8–10 node stage in 1994, and at the mid-flowering stage in 1995. The lowest impact of inoculation was at the pod swell stage for both years. When inoculated at 8–10 nodes, mid-flowering and pod swell stages, M. pinodes reduced yield by 31, 24 and 19%, respectively, in 1994 and 33, 43 and 30%, respectively, in 1995. The 1000-seed weight was not affected by the timing of inoculation; however, all inoculations reduced seed weight in both years. Plant-to-seed transmission of M. pinodes was affected by the timing of inoculation in 1994, but not in 1995. Results of this study suggest that prevention of early infection by M. pinodes will provide the best economic return in a mycosphaerella blight control program on field pea. Key words: Mycosphaerella blight, Mycosphaerella pinodes, field pea, Pisum sativum, yield reduction
Hysyn120 CS summer turnip rape
Authors: Stoenescu F. M. , Falk K. C.
Published: April 2011

Hysyn120 CS summer turnip rape (Brassica rapa L.) is a high-yielding, canola-quality, population-synthetic (syn1) cultivar adapted to short and mid-season growing areas of western Canada. Key words: Turnip rape (summer), synthetic, cultivar description
Effects of row spacing, seeding rate and seed-placed phosphorus on root diseases of spring wheat and barley under zero tillage
Authors: Bailey K. L. , Lafond Guy P. , Domitruk Daryl
Published: April 2011

Changes in tillage and other agronomic practices have shown benefits of increased grain yield for many crops, but these changes may alter the micro-environment resulting in changes to populations of disease-causing agents and other micro-organisms. This study examined the effects of row spacing (10, 20, 30 cm), seeding rate (54, 108, 161 kg ha−1 for barley; 67, 134, 202 kg ha−1 for spring wheat) and seed-placed phosphorus (0, 8, 16 kg ha−1) on root diseases in spring wheat and barley using a zero-tillage production system in four environments. Root rot severity was assessed by visual ratings and the causal agents were identified. Analyses of variance indicated significant differences in root rot severity and the incidence of some causal agents for the main treatment effects (i.e. row spacing, seeding rate, seed-placed phosphorus) and no significant interactions between locations, years, and cultural practices. Contrasts of treatment means showed that higher rates of seeding decreased root rot severity and the incidence of Fusarium in wheat but these effects were small (less than 6%). The higher rates of monoammonium phosphate fertilizer reduced root rot severity in barley by 7% and the incidence of Gaeumannomyces graminis var. tritici in wheat by greater than 40%. Wider row spacings showed a small reduction of 6% in root rot severity in wheat but mostly had no effect on root diseases. Wheat yields were negatively associated with root rot severity in three of four environments. Fertility, root rot severity, and seeding rate had the greatest impact on wheat yield. Root diseases did not affect barley yields. Therefore, the use of wider row spacings and higher seeding rates with zero tillage practices will not lead to adverse effects on root diseases in wheat and barley. Phosphorus fertilizer should be used to reduce losses resulting from take-all disease in wheat. Key words: Zero tillage, cultural practices, common root rot, take-all, cereals
Airborne off-target losses and deposition characteristics from a self-propelled, high speed and high clearance ground sprayer
Authors: Grover Raj , Maybank John , Caldwell Brian C. , Wolf Thomas M.
Published: April 2011

In order to quantify the drift and deposition characteristics of a self-propelled, high-speed, and high-clearance sprayer, a series of 15 field trials was carried out applying a herbicide:dye mix along a test swath. Three different types of nozzle tips were used, an XR11002 (Extended Range XR Teejet®), and two "low-drift" tips, a DG11002 (Drift Guard Teejet®) and a TT11002 (Turbo Teejet®). On-swath and off-swath deposits were sampled using petri-dish collectors, while the airborne cloud was sampled 5 m downwind of the swath using Rotorod® samplers. In wind speeds of 10 to 31 km h−1, airborne droplet drift was reduced by a factor of two with both "low drift" designs. The differences in the behaviour of the two low-drift tips from the standard tips were attributed to reductions in the total volume emitted as drift-prone droplets by the low-drift tips, resulting from their inherent design characteristics. On-swath deposit uniformity was best with the DG11002 tips and worst with the TT11002 tips, with the XR11002 tips being intermediate. Off-swath-deposits increased with wind speed. Off-swath deposits between 5 and 10 m were proportional to the total airborne mass at 5 m. Key words: Pesticide, Spra-Coupe, droplet drift, flat-fan tips, deposition variability, droplet size, droplet volume
CDC Clair winter wheat
Authors: Fowler D. B.
Published: April 2011

CDC Clair is a high-yielding, strong-strawed, semidwarf winter wheat (Triticum aestivum L.) with good winterhardiness. When grown in western Canada, it has the high grain yield and agronomic performance of CDC Kestrel, but improved grain quality. The grain protein concentration of CDC Clair has been higher than that of CDC Kestrel and similar to Norstar. CDC Clair is eligible for grades of the Canada Western Red Winter Wheat class. Key words: Triticum aestivum L., cultivar description, wheat (winter)
CDC Kestrel winter wheat
Authors: Fowler D. B.
Published: April 2011

CDC Kestrel is a lodging-resistant, high-yielding, semidwarf winter wheat with good winterhardiness and rust tolerance that is superior to Norstar. CDC Kestrel is eligible for grades of the Canada Western Red Winter Wheat class. Key words: Triticum aestivum L., cultivar description, wheat (winter)
AC Boreal summer turnip rape
Authors: Falk K. C.
Published: April 2011

AC Boreal summer turnip rape (Brassica rapa L.) is a canola quality population-synthetic (syn1) cultivar with very high seed oil and meal protein content adapted to the mid-season growing areas of western Canada. Key words: Turnip rape (summer), synthetic, cultivar description
Physiological responses of plants to salinity: A review
Authors: Volkmar K. M. , Hu Y. , Steppuhn H.
Published: April 2011

Root-zone salinization presents a challenge to plant productivity that is effectively countered by salt-tolerant halophytic plants, but unfortunately, much less successfully by major crop plants. The way in which salt affects plant metabolism is reviewed. Cellular events triggered by salinity, namely salt compartmentation, osmotic adjustment and cell wall hardening are connected to the whole plant responses, namely leaf necrosis, altered phenology and ultimately plant death. The roles of ion exclusion and K/Na discrimination in mediating crop response to salt appear to be central to the tolerance response, but they are by no means essential. The processes involved in regulating ion uptake at the membrane level are considered. Recent work elucidating the interaction between calcium and salinity tolerance is reviewed. Key words: Cell growth, cell turgor, ion regulation, K+/Na+ discrimination, osmotic adjustment, salt tolerance
Response of alfalfa to inoculation with Penicillium bilaii (Provide)
Authors: Beckie H. J. , Schlechte D. , Moulin A. P. , Gleddie S. C. , Pulkinen D. A.
Published: April 2011

Yield and phosphorus (P) uptake response of alfalfa (Medicago sativa L.) to inoculation with Penicillium bilaii (Provide) at varying rates of P fertilizer, was determined in small- and large-plot experiments located in the Dark Brown, Black or Gray soil climatic zones of Saskatchewan and Alberta from 1994 to 1996. Soil at the sites contained low to medium levels of available P. In the establishment year of the small-plot experiments, inoculation of alfalfa with P. bilaii increased yields and P uptake by 3 to 18%, when averaged across P fertilizer rates. The largest response to inoculation occurred early in the growing season. In the year following establishment, yield and P uptake of inoculated alfalfa averaged 3% greater than uninoculated plants. In the establishment year of the large-plot experiment in 1994 and 1995, yields and P uptake of inoculated alfalfa at 10% bloom were 7 and 26% greater than uninoculated plants, when grown without and with a wheat (Triticum aestivum L.) companion crop, respectively. Unlike the small-plot experiment, alfalfa in the year following establishment did not respond to inoculation performed the previous year. The P credit (P fertilizer replacement value) of P. bilaii inoculation, based on yield response in the establishment year and in the year following establishment, averaged 4.6 kg P ha−1 in the small-plot experiments and 5.3 kg P ha−1 in the large-plot experiments. Tillage cropping practices that conserve water near the soil surface, and inclusion of a companion crop, may increase the probability of alfalfa response to P. bilaii inoculation as well as the efficacy of that response. Key words: Medicago sativa, Penicillium bilaii, Rhizobium meliloti, Triticum aestivum, phosphorus
Population bulk versus F1-derived family methods of yield testing in early generations of multiple-parent interracial and inter-gene-pool crosses of common bean
Authors: Singh Shree P. , Terán Henry
Published: April 2011

To simultaneously improve qualitative and quantitative agronomic traits, markers and gamete selection can be used. However, the effectiveness of alternative methods of yield testing in early generations must first be investigated. In this study, we therefore determined the relationships between seed yield of F1-derived families and of population bulks in F2 and F3 generations. We also compared seed yields of a high-versus low-yielding population in F2 and F3 with their advanced generation (F7) lines. First, we yield-tested 25 multiple-parent, interracial and inter-gene-pool populations, each represented by their population bulk, and 24 F1-derived families, at three locations, in F2 (1993) and F3 (1994). Each plot of the bulk of each population consisted of four rows and was replicated twice. The 24 F1-derived families were randomly divided into six groups of four. The four families of each group were sown together to represent one plot of each replication. But each family was harvested separately and the mean yield of the four families represented the plot yield. Then, based on the mean seed yield of F2 and F3, one comparatively high-yielding and one low-yielding population were selected. Ten F4-derived F7 lines from each population were yield tested at the same three locations in 1995–1996. Positive correlations were found between the mean seed yields of F2 and F3, and between the seed yield of population bulks and the yields of F1-derived families in both F2 and F3. The mean seed yield of the 10 F4.7 lines from the high-yielding population was significantly higher (P < 0.05) than that of its counterpart from the low-yielding population. Marker-assisted gamete selection for qualitative traits during hybridization and population development in the F1 can therefore be combined with yield selection among F1-derived families in early generations of common bean populations. Key words: Common bean, Phaseolus vulgaris L., gamete selection, early generation yield testing
AC Crystal red spring wheat
Authors: Fernandez M. R. , DePauw R. M. , Knox R. E. , Clarke J. M. , McCaig T. N. , McLeod J. G.
Published: April 2011

AC Crystal is a red-seeded spring wheat (Triticum aestivum L.). In combining high grain yield and resistance to prevalent races of common bunt in a semidwarf, photoperiod-insensitive background it is similar to AC Taber. It has improvements relative to AC Taber: resistance to prevalent races of loose smut, except race T9, and stronger gluten properties. AC Crystal has improved resistance to leaf spots compared to Neepawa, AC Karma, and AC Foremost. It is eligible for grades of the Canada Prairie Spring (Red) wheat class. Key words: Triticum aestivum L., cultivar description, loose smut resistance, common bunt resistance, high yield, red spring wheat
Influence de la fourniture en assimilats sur la maturation et la qualité de la pêche (Prunus persica L. 'Suncrest')
Authors: Souty M. , Génard M. , Reich Maryse , Albagnac G.
Published: April 2011

Maturity and sensory evaluation of peach (cv. Suncrest) fruits were evaluated in response to three leaf:fruit ratios, 6, 18 and 30, respectively. Fruit growth rates increased with increasing leaf:fruit ratios so that, at maturity, fruit weights of 75, 140 and 180 g were obtained from the three treatments, respectively. Metabolic activity (oxygen consumption) although indifferent between treatments when fruits were immature, segregated according to leaf:fruit ratios as fruits matured. Autocatalytic production of ethylene was delayed in fruits suffering from nutritional stress and the intensity of ethylene production was also dependent on assimilate supply. Sugars, especially sucrose, accumulated at slower rates when assimilate supply was lowest, i.e. six leaves per fruit. Malic and citric acids metabolisms were influenced by the leaves:fruit ratios. Quinic and shikimic acid levels were reduced according to the treatments. Key words: Peach, ripening, quality, assimilates, metabolic activity, sugars, acids
OAC Thames soybean
Authors: Tanner J. W. , Luzzi B. M. , Montminy W. , Gostovic P. , Hume D. J.
Published: April 2011

Thames is a 3025 CHU soybean (Glycine max [L.] Merr.) cultivar that had slightly higher yields than the mean of the checks, similar plant height, low lodging and high seed oil content. Key words: Soybean, cultivar description
Genetic and seasonal variation in the sinapine content of seed from Brassica and Sinapis species
Authors: Wang Shawn X. , Oomah B. Dave , McGregor D. Ian , Downey R. Keith
Published: April 2011

Seeds of 25 strains and cultivars of five Brassica species, (B. rapa, B. nigra, B. napus, B. juncea, B. carinata) and Sinapis alba field grown at Saskatoon in 1990 and 1991 were analyzed by high performance liquid chromatography (HPLC) for sinapine content. Significant genetic variation of sinapine content per seed was found among the species tested. The variation in sinapine content per seed was much greater than for sinapine concentration of oil-free meal. Sinapine content per seed was positively correlated with seed size. The interaction of species and year was only significant for sinapine content per seed (α = 0.05). Variation in sinapine concentration of oil-free meal was mainly due to genetic variability, and environmental effects were relatively small. Thus, it should be possible to select for low sinapine in the Brassica oilseed crops, merely by selecting for low sinapine concentration of oil-free meal. Key words: Sinapine content, genetic variability, environmental effect, Brassica species, Sinapis alba
White lupin: An alternative to pea in oat-legume forage mixtures grown in Newfoundland
Authors: McKenzie D. B. , Spaner D.
Published: April 2011

"Peas-oats-vetch" is a traditional annual forage crop in Newfoundland, cut as needed in late fall, and fed as fresh feed. We tested the potential of increasing yield biomass and N concentration of the annual forage mixture through the substitution of white lupin (Lupinus albus L.) for pea (Pisum sativum L.) in 1990 and 1991. On mineral soils, lupin and pea were seeded at rates of 10, 20, 40, and 80 seeds m−2 in 132 seeds m−2 oat (Avena sativa L.) mixtures, and compared with pure-stand oat. Oat-lupin and oat-pea mixtures, planted at similar seeding rates, were also harvested at weekly intervals between 8 and 14 wk after planting. Oat-lupin, oat-pea and pure-stand oat were evaluated in an additional experiment on peat soils. On mineral soils, oat-lupin mixtures yielded forage with similar, or greater, dry matter yields and N concentration than pure-stand oats and oat-pea mixtures. Greatest yields were attained when mixtures were planted with 20 to 40 lupin seeds m−2, and harvested 10 to 12 wk after early summer planting. On peat soils, white lupins were susceptible to diseases that did not affect peas, resulting in oat-lupin yields that did not differ from pure-stand oats. White lupin can be considered an alternative legume in oat-legume mixtures grown on mineral soils in eastern Newfoundland. Key words: Lupinus albus L., Pisum sativum L., oat-legume forage, podzolic soil, peat soil
Presentation of scientific data through multimedia
Authors: Smith Donald L.
Published: April 2011

Multimedia is the combination of images, sound and motion. This offers some exciting and potentially very useful opportunities for the presentation of scientific data, although it also offers potential for excesses that will distract from the message. Of the three components, sound is probably the most easily overused. The exact choice of techniques will vary with the audience, the most likely types for scientific data being researchers, students, practioners (in the case of agriculture, producers) and industry personnel. The electronic nature of multimedia allows alternate venues for a presentation, such as internet conferences, where the audience may view the presentation one at a time. In this case interactivity, non-linearity and hyperlinking become keys. They allow complete flexibility in the way a member of the audience approaches the talk. Those with more background may choose not to explore lateral sections providing additional detail in methods or background. The use of these techniques is just beginning a rapid expansion. At this time there are still several drawbacks. Projection facilities are few and a system problem may terminate your presentation. In addition, the quality of images is not yet as high as is the case with slides. However, these problems are rapidly disappearing. Key words: Multimedia, scientific data, hardware, software, presentation
AC Watson flax
Authors: Kenaschuk E. O. , Rashid K. Y.
Published: April 2011

AC Watson, a medium–early maturing oilseed flax (Linum usitatissimum L.) was released in 1997 by Agriculture and Agri-Food Canada, Research Centre, Morden, Manitoba. The cultivar has high oil quality, medium-large seed size, good lodging resistance, and with good yielding in both early and late seeding in the Black and the Brown Soil zones of the prairies. It is immune to North American races of rust caused by Melampsora lini and moderately resistant to wilt caused by Fusarium oxysporum f. sp. lini. Key words: Flax, oilseed, Linum usitatissimum L., cultivar description
Can cows and fish co-exist?
Authors: Fitch L. , Adams B. W.
Published: April 2011

Our paper provides an ecological perspective on the interrelationship between livestock grazing and riparian areas through a review of topical literature. We also describe the Alberta Riparian Habitat Management Project (also known as "Cows and Fish"), and draw upon our experience to provide a perspective on future riparian management actions. Those actions should begin with an understanding that prairie landscapes evolved with herbivores, in a grazing regime timed and controlled by season and climatic fluctuations where grazing by native grazers was followed by variable rest periods. Prevailing range management principles represent an attempt to imitate the natural system and describe ecologically based grazing systems. Traditionally, range management guidelines have focused on grazing practices and impacts in upland, terrestrial rangelands, with a lack of attention devoted to riparian areas.Three decades of riparian investigation have quantified the effect unmanaged livestock grazing can have on range productivity and watershed function. We contend that suitable grazing strategies for riparian areas will be developed first by understanding the function of riparian systems and then by applying range management principles to develop riparian grazing strategies. A key step towards determining the fit of livestock grazing is an understanding of the formation of riparian systems and their ecological function. We describe riparian structure, function and process to provide linkages between livestock grazing, riparian vegetation health and stream channel dynamics. We summarize the effects of unmanaged livestock grazing on riparian habitats and fish and wildlife populations. The general conclusion is that unmanaged grazing results in overuse and degradation of riparian areas. The literature provides several options for the development of riparian grazing strategies. We provide an overview of strategies suitable for riparian areas in Southern Alberta which should maintain ecological function and sustained use. Key words: Riparian, grazing management, grazing systems, riparian grazing
Effects of low-temperature stress on development of winter crown rot in first-year alfalfa
Authors: Hwang S. F. , Gaudet D. A.
Published: April 2011

The effects of sub-lethal low temperatures on predisposing first-year alfalfa plants to infection by the low temperature basidiomycete (LTB), and the effects of sub-lethal winter crown rot levels on alfalfa cold hardiness were evaluated in controlled environment and field studies. Alfalfa, subjected to the sublethal stress temperature of –7.5 °C for 1 to 5 wk and inoculated with LTB, exhibited higher mortality, lower shoot dry weights, and higher winter crown rot levels than alfalfa similarly inoculated but non-stressed. Inoculation and incubation of alfalfa with the LTB fungus for 4 wk decreased the freezing resistance of cv. Barrier and cv. Peace alfalfa by 26 and 32%, respectively, compared with the non-inoculated controls. Following inoculation and incubation with LTB, stress temperatures between −6 and −15 °C increased LTB induced mortality in Barrier by 17–54% and in Peace by 10–75%. These results demonstrate that sub-lethal low-temperature stress can act synergistically with winter crown rot pathogen to reduce survival and yield in first-year alfalfa. Key words: Medicago sativa L., alfalfa, low temperature, winter crown rot, Coprinus psychromorbidus
Evaluation of determinate and indeterminate pinto bean cultivars under an available soil moisture gradient
Authors: Nleya T. M. , Slinkard A. E. , Vandenberg A.
Published: April 2011

Determinate dry bean (Phaseolus vulgaris L.) cultivars are preferred under irrigation in western Canada. Expansion of dry bean production into dryland areas in western Canada requires re-evaluation of the best growth habit. The objective of this study was to compare determinate and indeterminate pinto bean cultivars for seed yield and other agronomic traits under a soil moisture gradient. Six pinto bean cultivars, three determinate and three indeterminate, were grown under an available soil moisture gradient in Saskatoon SK, Canada at one environment in 1993 and at two environments in 1994. An increase in available soil moisture, induced by growing rows of pinto bean plants at increasing distances from a spring-seeded winter barley (Hordeum vulgare L.) strip, increased number of pods per plant, plant height, seed weight, seed yield and seed nitrogen concentration for both determinate and indeterminate cultivars of pinto bean. Indeterminate cultivars, however, were taller and higher yielding than determinate cultivars at every level of soil moisture under these dryland conditions. Key words: Phaseolus vulgaris, dry bean, pinto bean, soil moisture, drought stress