bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of growth, yield, and fruit size of chokecherry, pincherry, highbush cranberry, and black currant cultivars in Saskatchewan
Authors: St-Pierre R. G. , Zatylny A. M. , Tulloch H. P.
Published: April 2011

The objective of this study was to quantitatively characterize the growth, yield and fruit size of cultivars of chokecherry (Prunus virginiana L.), pincherry (Prunus pensylvanica L.f.), highbush cranberry (Viburnum trilobum Marsh.), and black currant (Ribes nigrum L.). Cultivars were evaluated in replicated trials at two sites (Saskatoon and Outlook) in Saskatchewan over 2–5 yr. Espenant, Garrington, Lee Red, and Boughen Yellow were among the highest yielding of the chokecherry cultivars (mean yield = 7.2 kg plant-1 at Saskatoon); of these, Lee Red had the largest fruit. The pincherry cultivar Lee #4 (mean yield = 3.1 kg plant-1) yielded at least twice as much as Mary Liss or Jumping Pound. Highbush cranberry cultivars Alaska, Espenant, Garry Pink, Manitou, and Wentworth averaged yields of 2.0 kg plant-1 at Saskatoon. Of these, Manitou had the largest fruit. Two black currant trials were established; the cultivars included in the second trial were not available at the time of establishment of the first trial. Black currant yields ranged from 0.2 kg plant-1 for Willoughby to 1.0 kg plant-1 for Consort in the first trial, and from 0.2 kg plant-1 for the selection 4-24-29 to 2.0 kg plant-1 for McGinnis Black in the second trial. Black currant cultivars with the largest fruit size included Wellington, Topsy, and three numbered selections from the University of Saskatchewan (mean = 225 fruit/cup) in the first trial, and Ben Sarek, McGinnis Black, and Ben Alder (mean = 156 fruit/cup) in the second trial. Data from the current study provide a basis on which to evaluate the performance of currently available cultivars, and any new cultivars or future selections that may be developed. Key words: Prunus virginiana, Prunus pensylvanica, Viburnum trilobum, Ribes nigrum, fruit size, shoot growth, cultivar evaluation
Ultrastructural-chemical makeup of yellow-seeded (Brassica rapa) and brown-seeded (Brassica napus) canola within cellular dimensions, explored with synchrotron reflection FTIR microspectroscopy
Authors: Yu Peiqiang , Christensen Colleen R , Christensen David A , McKinnon John J
Published: April 2011

Synchrotron-based FTIR micro spectroscopy, developed recently as a novel, rapid and non-destructive analytical technique, could reveal chemical information of the intrinsic microstructures of biological tissues at ultra-spatial resolution. The objective of this study was to use synchrotron reflection FTIR microspectroscopy to explore chemical makeup (functional group and bonding characteristics) of ultrastructural tissues within cellular dimensions (10 µm × 10 µm) of yellow-seeded (Brassica rapa ‘Klondike’) and brown-seeded (Brassica napus ‘Bounty’) canola. The results showed that the ratios of total CH2:CH3, CH3-asymmetric:CH3-symmetric, CH2-asymmetric:CH2-symmetric and total CH-asymmetric:CH-symmetric were 1.06 and 1.13, 1.28 and 1.26, 2.90 and 3.08, 1.82 and 1.78, for the yellow-seeded and brown-seeded canola, respectively. There were no differences between the two canola types in the content and ratios of CH groups (CH2 and CH3) of the scanned areas, indicating that lipid chain length and branching are similar between the two seed types. There were significant differences in amide I and total CHO, indicating different microstructural protein (peptide C=O bonding) and carbohydrate makeup between the two canola types. The results also show differences in the ratios of total NH and OH:CHO (2.85 vs. 3.84, P < 0.01), total CH:total CHO (0.23 vs. 0.32, P < 0.01), amide I:NH and OH (0.48 vs. 0.37, P = 0.07), amide I:hemiceullulose (P = 0.09), hemicellulose:total CHO (0.039 vs. 0.059, P < 0.001), CHO:amide I (1.11 vs. 0.84, P = 0.051) between the yellow-seeded and brown-seeded canola, and indicate that the chemical makeup of the microstructure differs between the yellow-seeded (Brassica rapa) and brown-seeded (Brassica napus) canola type. In conclusion, this study indicates that synchrotron-based reflection FTIR microspectroscopy can be used to identify microstructural-chemical features of canola tissue. More detailed study is required to define the extent of differences that exist between the yellow-seeded (Brassica rapa) vs. dark-brownseeded (Brassica napus) canola. Such information on the microstructural-chemical features can be used by canola breeding programs to select superior varieties of canola for special purposes, and for predicting canola quality and nutritive value for humans and animals. Key words: Synchrotron, reflection infrared microspectroscopy, functional groups, chemical makeup, ultrastructure, canola, feed structure and chemistry
The biology of Canadian weeds. 132. Raphanus raphanistrum L.
Authors: Warwick Suzanne I , Francis Ardath
Published: April 2011

A review of biological information is provided for Raphanus raphanistrum L. Native to the Mediterranean region, the species is widely introduced and naturalized in temperate regions around the world. In Canada, it currently occurs in all provinces except Saskatchewan and Manitoba, has only a limited distribution in Alberta, and is also absent from the Yukon, the Northwest Territories and Nunavut. It is most abundant in the Atlantic and Pacific regions and is an important weed of field crops in the Maritime provinces and Quebec. A persistent seed bank, competitive annual growth habit and high fecundity all contribute to its weedy nature and ensure that it will be a continuing problem. It can easily hybridize with cultivated radish, R. sativus L., and commonly does so when they occur together. Limited hybridization with canola, Brassica napus L., has been reported from several experimental field and greenhouse trials. Selective herbicide control is most difficult in canola and other cruciferous crops. It is the most important dicot weed in the southwestern region of Australia, primarily due to the evolution of several different herbicide-resistant biotypes. These include biotypes resistant to the acetolactate synthase (ALS)-inhibitors (group 2 herbicides) and/or photosystem II-inhibitors (group 5), and a biotype with multiple resistance to ALS-inhibitors, photosystem II-inhibitors, an auxin (2,4-D amine), and a phytoene desaturase (PSDS)-inhibitor (diflufenican). A biotype resistant to the ALS-inhibiting herbicide chlorsulfuron has also been detected in South Africa. Key words: Wild radish, Raphanus raphanistrum, herbicide resistance, canola, hybridization, RAPRA
A review of sulphur fertilizer management for optimum yield and quality of canola in the Canadian Great Plains
Authors: Malhi Sukhdev S. , Schoenau Jeff J. , Grant Cynthia A.
Published: April 2011

In the Parkland region of the Canadian prairies, Canola (Brassica napus L. or Brassica rapa L.) is an important cash crop. Canola has a high requirement for sulphur (S). However, many soils in this region are deficient or potentially deficient in plant-available S for optimum canola seed yield. Application of sulphate-S at about 15–30 kg S ha-1 is usually sufficient to prevent S deficiency in canola on most of the S-deficient soils. Application of sulphate-S to canola at seeding time gives the highest increase in yield and S uptake. Deficiencies of S in canola plants can be prevented and/or corrected and seed yield improved with the use of sulphate-S fertilizers in the growing season. Application of sulphate-S at bolting can substantially restore seed yield, while an application at early flowering can moderately correct S deficiency damage. Side-banding is the most effective way to apply sulphate-S fertilizers to produce maximum seed yield and to prevent any damage to canola seedlings from seed-row placement. In relatively moist areas, broadcast-incorporation methods can produce seed yield similar to side-banding in most years.

Elemental S fertilizers were not effective in increasing seed yield in the year of application, and were generally less effective than sulphate-S fertilizer even after multiyear annual applications, especially when applied in spring. Autumn-applied elemental S was more effective than spring-applied elemental S. Banding delayed availability of elemental S as compared to broadcast application. Use of granular elemental S products is not reliable for optimum seed yield of canola under Canadian prairie conditions on S-deficient soils, particularly in the initial year and with spring application or band placement. Elemental S fertilizers may have a role to maintain or build-up sulphate-S levels in soils marginally low in S where residual benefits are desirable, but management decisions should consider both immediate and long-term effects of S fertilizer on seed yield, seed quality and economics. The findings suggest the need of future research to increase dispersion and distribution of S particles from granules for faster oxidation of elemental S in soil, and to develop elemental S fertilizer products/formulations that can be used on a commercial scale to prevent and/or correct S deficiency in the growing season to optimize seed yield and quality of canola. Research is also required to determine the long-term effects of balanced application of S with other nutrients on soil quality, accumulation and distribution of nitrate-N, sulphate-S and other nutrients in the soil profile, efficiency of nutrient, water and energy use, and crop diseases. More research should be conducted in relation to soil/plant tissue testing issues for optimum seed yield and quality of canola. Key words: Balanced fertilization, canola, elemental S fertilizers, method of application, rate of S, seed quality, seed yield, sulphate-S fertilizers
Influence of propagation method a nd indole-3-butyric acid on growth and development of in vitro- and ex vitro-derived lingonberry plants
Authors: Debnath Samir C
Published: April 2011

The effects of two propagation methods and four indole-3-butyric acid (IBA) concentrations were studied in two cultivars of lingonberry (Vaccinium vitis-idaea L.). Cultivars Regal and Erntedank, propagated by conventional softwood cuttings (SC) and adventitious shoot regeneration from excised leaves of micropropagated shoots (LC), were evaluated for growth and morphology. Significant two- and three-way interactions for shoot and rhizome characteristics were observed among the treatments. The LC plants produced shorter and less-vigorous shoots but had more stems, branches, leaves and rhizomes in contrast to conventional cuttings, which rarely produced rhizomes. IBA had an effect on shoot and rhizome morphology, but not on the frequency of rhizome formation. In vitro culture on zeatin-containing nutrient medium apparently induces the juvenile branching characteristics that favored enhanced rhizome production. The advantage of shoot and rhizome production of adventitiously produced LC plants over SC plants varied between the genotypes. Erntedank plants had better shoot growth and rhizome development across propagation methods than did Regal plants. Key words: Vaccinium vitis-idaea, propagation, regeneration, cuttings, indole-3-butyric acid
CDC Frontier kabuli chickpea
Authors: Warkentin Tom , Banniza Sabine , Vandenberg Albert
Published: April 2011

CDC Frontier, a kabuli chickpea (Cicer arietinum L.) cultivar, was released in 2003 by the Crop Development Centre, University of Saskatchewan, for distribution to Select seed growers in western Canada through the Variety Release Program of the Saskatchewan Pulse Growers. CDC Frontier has a pinnate leaf type, fair ascochyta blight [Ascochyta rabiei (Pass.) Labr.] resistance, medium maturity, medium-large seed size and high yield potential in the Brown and Dark Brown soil zones of the Canadian prairies. Key words: Chickpea, Cicer arietinum L., cultivar description, ascochyta blight
Cabbage seedpod weevil resistance in canola (Brassica Napus L.) yellow mustard (Sinapis alba L.) and canola × yellow mustard hybrids
Authors: Ross Daniel W. , Brown Jack , McCaffrey Joseph P. , Harmon Bradley L. , Davis Jim B.
Published: April 2011

Canola, yellow mustard and yellow mustard × canola hybrids were screened for resistance to Ceutorhynchus obstrictus (Marsham) in a series of greenhouse and laboratory choice tests. Tests were conducted using small and large cages designed to hold Brassica pods or whole plants, respectively, with ovipositing female C. obstrictus. Pods were examined for feeding punctures, eggs laid and exit holes that resulted from emerging larvae. All yellow mustard cultivars examined were highly resistant to C. obstrictus feeding and egg laying. In addition, hybrid lines were found with significantly reduced feeding punctures, oviposition, and exit holes compared with canola. A negative relationship was observed between total glucosinolate content of seed and C. obstrictus resistance; however, in both detached pod and whole plant choice tests, hybrids were identified with high seed glucosinolate content that were more susceptible than the most susceptible canola. The relatively poor association between total seed meal glucosinolate content and C. obstrictus resistance is highly important and plant breeders should be able to develop canola-quality oil and seed meal characteristics with improved C. obstrictus resistance using yellow mustard × canola hybrids. The effect of specific glucosinolate types on C. obstrictus resistance may be more complex than previously thought, and further research will be needed to better understand the relationship between specific glucosinolate types and resistance to C. obstrictus. Key words: Brassica napus, Sinapis alba, Ceutorhynchus obstrictus, cabbage seedpod weevil, insect resistance, glucosinolate
Nass hard red spring wheat
Authors: Nass H. G. , Caldwell C. D. , Price M. A.
Published: April 2011

Nass, a hard red, medium blend, spring milling wheat (Triticum aestivum L. em. Thell.), is adapted to Ontario, Quebec and the Maritimes. It has expressed high grain yield, good lodging resistance, a high level of resistance to powdery mildew, and a much higher than average resistance to fusarium head blight (FHB). Key words: Triticum aestivum, hard red spring wheat, yield, cultivar description, Fusarium head blight
Inheritance of multiple herbicide resistance in wild oat (Avena fatua L.)
Authors: Karlowsky Jocelyn D , Brûlé-Babel Anita L , Friesen Lyle F , Van Acker Rene C , Crow Gary H
Published: April 2011

To gain some insight into the surprisingly frequent occurrence of multiple herbicide resistant wild oat in western Canada, the inheritance of multiple herbicide resistance was studied in two wild oat (Avena fatua L.) populations, UMWO12-01 and UMWO12-03, from Manitoba, Canada. Both populations are resistant to each of three distinct herbicides, imazametha benz-methyl, flamprop-methyl, and fenoxaprop-p-ethyl (hereafter referred to as imazamethabenz, flamprop, and fenoxaprop-P, respectively). Crosses were made between each resistant (R) population and a susceptible (S) wild oat population (UM5) (R/S crosses), and between the two resistant populations (R/R crosses). Subsets of parental, F2 plants, and F2-derived F3 (F2:3) families were treated separately with each of the three herbicides and classified as R or S for individual plants, and homozygous R, segregating, or homozygous S for F2:3 families. F2 plants and F2:3 families from R/S crosses segregated in 3R:1S and 1 homozygous R:2 segregating:1 homozygous S ratios, respectively. These ratios indicate that a single dominant or semi-dominant nuclear gene controls resistance to each of these herbicides in each population. F2 plants and F2:3 families from R/R crosses segregated for resistance/susceptibility when treated with either imazamethabenz or flamprop. Therefore, the genes for resistance to these two herbicides are different in each R population. Individual F2:3 family response demonstrated that the genes were not independent of each other, indicating possible linkage between the genes for resistance to each herbicide. Genetic linkage could explain how the wild oat populations developed multiple resistance in the absence of selection by two of the herbicides, imazamethabenz and flamprop. Key words: Wild oat, Avena fatua, herbicide resistance, genetics of resistance, multiple resistance
Influence of weather on apricot, peach and sweet cherry production in the Okanagan Valley of British Columbia
Authors: Caprio J. M. , Quamme H. A.
Published: April 2011

An iterative χ2 method that generates indices of association was used to determine daily weather occurrences associated with annual variations in peach (Prunus persica Batch.), apricot (Prunus armeniaca L.), and sweet cherry production (Prunus avium L.) in the Okanagan Valley of British Columbia over a 72 yr period, 1920–1991. During September and early October of the pre-harvest year, warm daytime temperatures favoured apricot (≥ 26°C) and sweet cherry production (≥ 19°C), probably because this promoted flower bud development. High daytime temperatures (≥ 27°C) were detrimental to apricot production in August of the pre-harvest year. During the pre-harvest year, peach production was only weakly associated with daytime temperature. Precipitation adversely affected peach and sweet cherry production in the preharvest year indirectly by associated lower temperatures or directly by enhanced disease infection. The main climatic factor limiting production of these crops was low temperatures from November to February (critical value range, ≥ -13 to ≥ -24°C, nighttime temperature) that cause winter injury. Precipitation during this period, usually snowfall, mostly favoured production. Poor production years were also associated with low nighttime temperatures (≤ -2 to -5°C) in spring at the time the flowers are prone to frost injury. During the bloom period warm temperatures (≥16°C, daytime temperature) favoured Prunus production, probably because of the temperature requirements for good pollination and flower set. Rainfall during fruit development and harvest of sweet cherry reduced production because of rain-induced cracking. Daytime temperatures were detrimental to production of apricot (≥ 31°C) and sweet cherry (≥ 33°C to ≥ 37° C) during harvest. The anticipated climate change appears to favour Prunus production in the Okanagan Valley, except for increased rainfall on sweet cherry production. Key words: Prunus persica Batch., Prunus armeniaca L., Prunus avium L., tree fruit, climate, heat stress, spring frost, winter injury
Agronomic benefits of alfalfa mulch applied to organically managed spring wheat
Authors: Wiens M. J. , Entz M. H. , Martin R. C. , Hammermeister A. M.
Published: April 2011

Field experiments were established at two locations in Manitoba in 2002 and 2003 to determine N contribution, moisture conservation, and weed suppression by alfalfa mulch applied to spring wheat (Triticum aestivum L). Mulch treatments included mulch rate (amount harvested from an area 0.5×, 1× and 2× the wheat plot area), and mulch application timing (at wheat emergence or at three-leaf stage). Positive relationships were observed between mulch rate and wheat N uptake, grain yield, and grain protein concentration. At Winnipeg, the 2× mulch rates (3.9 to 5.2 t ha-1) produced grain yields equivalent to where 20 and 60 kg ha-1 of ammonium nitrate-N was applied in 2002 and 2003, respectively. Where mulch and ammonium nitrate produced equivalent grain yield, grain protein in mulch treatments was often higher than where chemical fertilizer was used. N uptake was also observed in the following oat (Avena sativa L.) crop. The highest mulch rate (2×) produced higher N uptake and grain yield of second-year oat compared with ammonium nitrate treatments. N use efficiency of mulch-supplied N by two crops over 2 yr [calculated as (treatment N uptake – control N uptake)/total N added] was between 11 and 68%. Mulch usually suppressed annual weeds, with greater suppression with late- than early-applied mulch. Increased soil moisture conservation was observed with high mulch rates (≥ 4.3 t ha-1) at three sites. Alfalfa mulch holds promise for low-input cropping systems when used on wheat at the 2× rates. Key words: Legume N, low-input farming, integrated weed management, wheat protein
The agronomic value of annual plant diversity in crop-weed systems
Authors: Szumigalski Anthony R. , Van Acker Rene C.
Published: April 2011

Enhanced crop or cultivar diversity within annual cropping systems could provide important ecological and agronomic benefits. The agronomic effects of annual plant diversity from mixtures of crop species and barley (Hordeum vulgare L.) cultivar types were compared using richness levels of 1, 2, 5 or 10 randomly selected taxa in a greenhouse experiment. Increasing crop richness increased overall crop dry matter production, production stability (i.e., decreased CV for dry matter production) and weed suppression. These agronomic variables tended to level off after a richness of five to six crop species, suggesting that further increases in crop diversity are redundant. Increasing barley cultivar richness increased crop production in one of two experimental runs, but no effects were observed for weed suppression. Increased light interception related to greater plant canopy height variation in diverse mixtures of species could have contributed to increased productivity in the crop richness experiment. The results of this study suggest that the ecological functions of diversity provide productivity, yield stability and weed suppression benefits for mixtures of crop species, and even perhaps for mixtures of cultivars within a given crop species. Key words: Diversity (crop), suppression (weed), stability (yield), intercropping, cultivars (barley), oat (wild)
Somerset hard red spring wheat
Authors: Fox S. L. , Townley-Smith T. F. , Humphreys D. G. , McCallum B. D. , Fetch T. G. , Gaudet D. A. , Gilbert J. A. , Menzies J. G. , Noll J. S. , Howes N. K.
Published: April 2011

Somerset is a hard red spring wheat that meets the end-use quality and kernel visual distinguishability specifications of the Canada Western Red Spring class. Evaluation of Somerset occurred in the Central Bread Wheat Cooperative Registration Test in 2001, 2002 and 2003 and was found to be adapted to the wheat-growing regions of the Canadian prairies. In comparison to the check cultivars Katepwa, McKenzie, CDC Teal, AC Barrie and Superb, Somerset grain yield was intermediate to AC Barrie and McKenzie. Somerset is resistant to stem rust, leaf rust and loose smut. Resistance to fusarium head blight was similar to that of AC Barrie, Katepwa and McKenzie. End-use quality tests identified that Somerset had about 1% more grain protein and slightly higher flour yield than the check cultivars. Somerset has lower test weight and is taller than the check cultivars. Key words: Triticum aestivum L., cultivar description, red spring wheat, grain protein
Canola response to high and moderately high temperature stresses during seed maturation
Authors: Aksouh-Harradj N M , Campbell L C , Mailer R J
Published: April 2011

Canola is a valuable oilseed crop worldwide. Temperature during the post-anthesis period plays an important role in determining the final yield and seed composition. Experiments were conducted in climate-controlled growth cabinets to test the effect of two high temperature regimes following a 24-h acclimation period on three canola cultivars differing in their thermotolerance. A long, moderately high temperature treatment of 28°C/23°C (day/night) was applied for 10 d from 20 to 30 d after flowering (DAF) and a short, very high temperature regime of 28°C/23°C (day/night) including a peak of 38 °C reached for 5 h around midday for 5 d from 25 to 29 DAF. Very high temperature for 5 d reduced yield on the main stem by up to 52% for a sensitive cultivar by reducing seed weight. This treatment also decreased the oil/protein ratio, but had a lesser effect on fatty acid composition. The moderately high temperature treatment for 10 d had only affected yield of one cultivar and increased the oil/protein ratio of all cultivars. However, it had a more pronounced effect on the fatty acid profile. A short period of very high temperature at a sensitive stage can be as critical to canola mild temperature stress over a longer period. Key words: Brassica napus, oil, protein, fatty acids, tolerance, acclimation, heat stress
The relationship between lodging and plant height in a diverse wheat population
Authors: Navabi A. , Iqbal M. , Strenzke K. , Spaner D.
Published: April 2011

We examined the genetic variation for lodging tolerance in different plant height groups, within a diverse population of wheat (Triticum aestivum L.) genotypes (n = 14 0). Lodging was artificially induced by dragging a weighted apparatus across plots twice during the season at early and late milk stages. Grain yield was negatively correlated with lodging, while lodging scores were positively correlated with plant height. Although plant height appeared to be the major contributor to lodging tolerance, some variation was also observed in taller plants. This suggests that genetic gain in lodging tolerance can be obtained, to some extent, independent of plant height. Key words: Plant height, lodging tolerance, Triticum aestivum L., CIMMYT, Canada
The Biology of Invasive Alien Plants in Canada. 4. Heracleum mantegazzianum Sommier & Levier
Authors: Page Nicholas A. , Wall Ronald E. , Darbyshire Stephen J. , Mulligan Gerald A.
Published: April 2011

Heracleum mantegazzianum (giant hogweed) is an invasive alien plant of management concern in southern Canada where it has escaped from horticulture and established and spread in natural, ruderal, and agricultural ecosystems. It poses a threat to natural ecosystems and human health, and is also a weed in agricultural and urban areas. It is a member of the Carrot family (Apiaceae) and is closely related to the native species Heracleum maximum Bartram (cow-parsnip). It is a monocarpic perennial, which generally flowers in its 3rd or 4th year. Large size, leaf shape, dark reddish pigments in patches on stems and petioles, and fruit characteristics readily distinguish H. mantegazzianum from other plants in Canada. It is increasingly common in riparian areas, floodplains, and forest edges in or near urban areas in southwestern British Columbia and southern Ontario. Based on herbarium specimens, H. mantegazzianum was first recorded in Ontario in 1949, British Columbia in 1964, Nova Scotia in 1980, Quebec in 1990, and New Brunswick in 2000. The development of dense stands of H. mantegazzianum can also reduce the richness of native plants. Contact with H. mantegazzianum can cause phytophotodermatitis, a serious skin inflammation caused by UV photo-activation of furanocoumarins present in the sap. Control methods include herbicide application, mechanical cutting, and animal grazing, but strategies to address seed dispersal and re-establishment from dormant seed must also be adopted. Widespread establishment in southern Canada suggests that eradication is unlikely. However, range expansion and rapid population growth can be prevented through strategic management including public education. Key words: Giant hogweed, Heracleum mantegazzianum, Apiaceae, HERMZ, invasive plant, weed biology, furanocoumarins
The Biology of Invasive Alien Plants in Canada. 5. Polygonum cuspidatum Sieb. & Zucc. [= Fallopia japonica (Houtt.) Ronse Decr.]
Authors: Barney Jacob N. , Tharayil Nishanth , DiTommaso Antonio , Bhowmik Prasanta C.
Published: April 2011

Polygonum cuspidatum (Japanese knotweed) is an introduced perennial geophyte in the buckwheat family (Polygonaceae). The phytogeographic distribution of P. cuspidatum in North America suggests a large number of intentional introductions via ornamental plantings from 1870 to 2000, followed by secondary spread from these foci. This species is most pernicious along riparian corridors and road and railroad rights-of-way, reducing visibility, displacing native species, negatively affecting native wildlife, and causing alterations in natural hydrologic processes. Although non-hybrid seed recruitment has not been observed in Europe because of the presence of male-sterile clones only, dispersal of seeds and stem and rhizome fragments by flowing water does occur in North America and populations are readily established from these sources. The primary means of local and regional range expansion is human-mediated transport of rhizome-infested soil. Hybridization is common with the congener P. sachalinense in the introduced ranges of North America and Europe resulting in the equally noxious P. × bohemicum. Key words: Japanese knotweed, Mexican bamboo, Polygonum, Fallopia, Reynoutria, POLCU, invasive plant, weed biology
Seeding rate and row spacing effect on weed competition, yield and quality of hemp in the Parkland region of Saskatchewan
Authors: Vera C. L. , Woods S. M. , Raney J. P.
Published: April 2011

Field experiments were conducted on a Black Chernozem silty loam soil at Melfort, Saskatchewan, Canada, from 2000 to 2002, to determine the effect of seeding rate and row spacing on weed competition, as well as on seed, shoot biomass production and seed q uality attributes of industrial hemp ( Cannabis sativa L. ‘Fasamo’ and ‘Finola’). Increasing seeding rate from 20 to 60 or 80 kg ha-1decreased weed density in all years (average of 33%) and reduced weed size (34%) in 2000. It also increased hemp plant density, biomass and seed yield (average of 174, 23 and 34%, respectively). Seed weight and protein were not affected by seeding rates, but seed oil content increased 1% in one year, when seeding rate increased from 20 to 60 kg ha-1. Row spacing (18 and 36 cm) had little or no definite effect on most of the parameters studied. Key words: Biomass, cultivar, hemp, protein content, oil content, organic farming, row spacing, seeding rate, weed competition
Comparative nitrogen response and economic evaluation for optimum yield of hybrid and open-pollinated canola
Authors: Mahli S. S. , Brandt S. , Ulrich D. , Lafond G. P. , Johnston A. M. , Zentner R. P.
Published: April 2011

Plant breeders have dramatically improved the yield potential of new canola cultivars. To achieve optimum yield with such cultivars, particularly hybrids, may require changes to fertilizer management practices that were established prior to development of these cultivars. We investigated the influence of N fertilizer rate (0, 30, 60, 90, 120, and 150 kg N ha-1) on plant density, days to flowering, length of flowering stage, days to maturity, biomass, seed yield and quality, and economic returns of two canola cultivars (Quantum, a high-yielding open-pollinated; and InVigor® 2663, a high-yielding hybrid) on a Dark Brown (Scott), a Thick Black (Melfort), and a Thin Black (Indian Head) Chernozem soil in Saskatchewan in 2000 and 2001. Plant density was slightly lower for InVigor 2663 than Quantum due to larger seed size of the former. InVigor 2663 tended to take more days to flowering and had shorter flowering stage duration compared with Quantum, but the two cultivars showed no consistent difference for the number of days to maturity. InVigor 2663 generally produced more biomass and seed yield than Quantum. Oil and protein concentration in seed were higher for InVigor 2663 than Quantum, with an opposite trend for the proportion of green seeds, indicating better seed quality for InVigor 2663. Addition of N tended to reduce plant density and decreased seed oil concentration, while it increased crop growth duration, seed protein concentration, seed yield and biomass. Under adequate N fertilization, InVigor 2663 provided greater net economic returns than Quantum under both moist and relatively dry conditions. In conclusion, InVigor 2663 performed better agronomically than Quantum, but the similar nature of seed yield response to applied N suggests that target N fertilizer rates for optimum seed yield and net economic returns should be similar for both cultivars based on this limited comparison of one hybrid and one open-pollinated canola cultivar under these soil-climatic conditions. Key words: Brassica napus L., hybrid canola, N rate, open-pollinated canola, seed quality, seed yield
Economic benefits of integrated weed management systems for field crops in the Dark Brown and Black soil zones of western Canada
Authors: Smith E. G. , Upadhyay B. M. , Blackshaw R. E. , Beckie H. J. , Harker K. N. , Clayton G. W.
Published: April 2011

Integrated weed management (IWM) systems that combine seeding date, seeding rate, herbicide rate, and timing of nitrogen (N) fertilizer application were assessed for their economic performance in the Dark Brown and Black soil zones. A barley-field pea IWM system in the Black soil zone at Lacombe, Alberta, and a wheat-canola IWM system in the Dark Brown soil zone at Lethbridge, Alberta, and Scott, Saskatchewan, were used to assess contributions of seeding date (April or May), seeding rate (recommended or 150% of recommended), fertilizer timing (fall or spring), and in-crop herbicide rate (50% or 100% of recommended). The factorial set of treatments was applied in 4 consecutive years at each site. For barley-field pea production, the highest contribution margin (CM) (returns over variable production costs) was earned with 50% of the recommended herbicide rate, spring application of N fertilizer, seeding barley later at the high seeding rate, and seeding field pea early at the recommended seeding rate. This IWM system had a CM benefit of at least $51 ha-1 compared with current common practices. The wheat-canola system results were site specific. At Lethbridge, it was more profitable to use 50% of recommended herbicide rates and to seed both crops early, with an early seeding date being very important for canola. The CM of this IWM system was $48 ha-1 higher than current common practices. At Scott, the wheat-canola system was more profitable with spring fertilizer application, 50% of the recommended herbicide rate, and an early seeding date for canola. The best IWM system had a CM $15 to $75 ha-1 higher, depending on the year, than common practices. Our results confirmed the economic merits of using IWM practices for cereal-oilseed and cereal-pulse cropping systems in these regions of western Canada. Key words: Economic, integrated weed management, contribution margin, canola, wheat, field pea, barley
Effect of seed treatments on emergence, yield, and root rot severity of soybean under Rhizoctonia solani inoculated field conditions in Ontario
Authors: Xue A. G. , Cober E. , Morrison M. J. , Voldeng H. D. , Ma B. L.
Published: April 2011

Field trials were conducted with soybean at two sites each year from 2001 to 2003 in Ottawa, ON, to determine the effect of seed treatments with various combinations of seven formulated fungicides and the bioagent Yield Shield (Bacillus pumilus GB34) under Rhizoctonia solani inoculated conditions. Controls were untreated seed planted into both non-inoculated (natural) soil and soil inoculated with R. solani. Compared with the non-inoculated control, inoculation significantly increased root rot severity and reduced emergence by 27%, and yield by 31%. Under the inoculated conditions, none of the seed treatments significantly increased emergence or yield in all of the six trials when compared with the control. Allegiance (metalaxyl) plus Vitaflo-280 (carbathiin plus thiram) and Vitaflo-280 alone were the most effective seed treatments, increasing emergence in by 20 and 19% and yield by 21 and 26%, which were significantly better than the control in four and five trials for emergence and three and four trials for yield, respectively. Allegiance plus HEC5725 (HEC5725), Apron Maxx RTA (fludioxonil plus metalaxyl), and Maxim 480FS (fludioxonil) increased both emergence and yield in two trials and TFL RTU (metalaxyl plus triflox ystrobin) plus Yield Shield in one trial. There was no difference between seed treatment with Allegiance and the untreated control for all parameters, confirming that metalaxyl is ineffective to R. solani. It is concluded that carbathiin, thiram, HEC5725, fludioxonil an trifloxystrobin are effective active ingredients protecting soybean from soil-borne R. solani and increasing plant emergence and yield. Key words: Rhizoctonia solani, seed treatment, soybean, Glycine max, fungicide, bioagent
Influence of agronomic traits on the expression of tissuespecific resistance to mycosphaerella blight in field pea
Authors: Conner R. L. , Hwang S. -F. , Woods S. M. , Chang K. F. , Bing D. J. , Su H. , McAndrew D. W. , Yager L. M.
Published: April 2011

Mycosphaerella blight, caused by Mycosphaerella pinodes, is the most destructive disease of field pea (Pisum sativum L.) in western Canada. A 3-yr field study conducted at two field locations examined the effect of differences in lodging, growth stage and maturity on disease development among field pea cultivars that possess different forms of partial resistance. Significant differences in disease development, measured as area under the disease progress curve (AUDPC), and as disease severity on the leaves, stems and pods were observed among the field pea cultivars. These measurements of disease development were only influenced by differences in crop maturity in 2005. Only cultivars that were either intermediate or late maturing had low disease severity ratings or AUDPC values. Differences in the degree of lodging had a small inconsistent effect on the mycosphaerella blight ratings. These results suggest that differences in maturity should be considered in order to avoid inadvertent selection for late maturity while evaluating field pea lines or cultivars for mycosphaerella blight resistance. Key words: Mycosphaerella pinodes, field pea, Pisum sativum, maturity, lodging.
Effect of nitrogen fertilizer rate, herbicide rate, and soil disturbance at seeding on the productivity of a wheat-pea rotation
Authors: Mohr R. M. , Derksen D. A. , Grant C. A. , McLaren D. L. , Monreal M. A. , Moulin A. M. , Khakbazan M. , Irvine R. B.
Published: April 2011

Rotational productivity is a function of the rotational crops and their interactions, as well as the management employed. Understanding the functioning of the overall production system, as well as its component parts, may contribute to improved management. Effects of nitrogen fertilizer rate (25, 50, 75, 100 kg N ha-1 as urea) and herbicide rate (66 or 100% of recommended) applied to wheat, and of the level of soil disturbance at seeding, on the productivity and N status of a 2-yr rotation of spring wheat (Triticum aestivum L.) and field pea (Pisum sativum L.) were assessed over two rotation cycles at two locations in southwestern Manitoba. Management factors typically acted independently to influence the cropping system. In both wheat and pea, high soil disturbance at seeding reduced or tended to reduce plant density in most site-years, resulting in reduced yields in about half of site-years. In 2 site-years where weed pressure was high, wheat yields for high disturbance treatments were less than 60% of low disturbance seeding, demonstrating the importance of adequate plant stands under sub-optimal growing conditions. The herbicide rate applied to wheat had few significant effects on wheat and pea. In most site-years, N fertilization had limited or negative effects on wheat yields due partly to relatively high soil NO3-N levels. Soil NO3-N levels declined over the years of the study, suggesting that N contributions from peas did not exceed crop N removal and/or N losses from the wheat-pea rotation. The N rate applied to wheat typically did not affect pea yields. Key words: Wheat, pea, rotation, herbicide, nitrogen, soil disturbance
Distribution of nitrogen uptake, fibrous roots and nitrogen in the soil profile for fresh-market and processing carrot cultivars
Authors: Westerveld Sean M , McKeown Alan W. , McDonald Mary Ruth
Published: April 2011

In temperate regions, yield of carrot [Daucus carota subsp. sativus (Hoffm.) Arkang.] is not generally affected by preplant applications of nitrogen (N). Previous studies speculate that carrots utilize N from much deeper in the soil profile than other crops. Carrot (cvs. Idaho and Fontana) were grown on organic and mineral soil in Ontario over a 3-yr period to determine rooting and N-uptake dynamics. Nitrogen application rates ranged from 0 to 200% of Ontario recommendations for each soil type. Soil samples collected at seeding and harvest at three depths were assessed for total N, nitrate-N and ammonium-N. The same cultivars were grown in 150-cm-deep PVC pipes filled with silica sand or soilless mix to assess root distribution and N uptake. Potassium nitrate fertilizer enriched with 15N was applied at three depths in the pipes and plants were assessed 28 d later for fertilizer N recovery. In the field, the highest N concentration both at seeding and at harvest was in the top 30 cm of the soil profile, but a significant pool of N was available at the 30–60 and 60–90 cm depths. In the pipes, up to 55% of the roots were below 30 cm depth, and these roots assimilated as much N as shallow roots. There were no differences between the cultivars in root distribution or timing of N uptake. Soil N at depths below 30 cm is available to carrots and contributes to plant growth. Soil sampling for N in the 30–60 cm depth is necessary for the determination of N fertilizer requirements. Key words: Daucus carota, rooting depth, fibrous roots, nitrate, ammonium, cultivar comparison
Effects of inoculum density, temperature, seeding depth, seeding date and fungicidal seed treatment on the impact of Rhizoctonia solani on lentil
Authors: Chang K. F. , Hwang S. F. , Gossen B. D. , Turnbull G. D. , Wang H. , Howard R. J.
Published: April 2011

Rhizoctonia solani causes seedling blight and root rot in lentil, which reduces plant populations and the vigour and yield of surviving plants. Factors in the seedling environment, such as inoculum density, temperature, seeding depth, seeding date, and fungicidal seed treatment were studied to determine the degree to which they affect the impact of R. solani on lentil seedlings. Survival of lentil plants was evaluated after planting into soil artificially inoculated with various concentrations of a highly aggressive isolate of R. solani (AG-4). Emergence, seedling survival and shoot dry matter production decreased with increasing inoculum density, but these declines varied with temperature. Low soil temperatures delayed the emergence of lentil seedlings in non-inoculated soil, but in inoculated soils, emergence was inhibited with increasing temperatures. Depth of seeding did not affect seedling establishment, but root rot severity increased with depth of seeding in a growth cabinet trial. Root nodulation was reduced as root rot severity increased. In field experiments carried out over 3 station years, seeding date had a substantial effect on seedling emergence and yield of inoculated treatments, but the trends were not consistent between sites. In field assessments of fungicide efficacy, treatment of seed with thiabendazole plus carbathiin (Crown) and carbathiin plus thiram (Vitaflo 280) improved seedling establishment relative to the inoculated control. Key words: Lens culinaris, damping-off, root rot, seeding date, fungicide seed treatment depth of seeding, thiabendazole, carbathiin, thiram
Water management strategies to enhance fruit solids and yield of drip irrigated processing tomato
Authors: Warner J. , Tan C. S. , Zhang T. Q.
Published: April 2011

Processing tomato (Lycopersicon esculentum Mill.) cv. H9553 was used to investigate the effects of water management strategies on fruit yield, quality and solids production in southwestern Ontario over a 3-yr period (2003-2005). Treatments included four levels of drip irrigation (1.2, 1.0, 0.8 and 0.5 of potential crop evapotranspiration, ETc) during the growing season, three preharvest water cutoff times (4, 3 and 2 wk preharvest) and an unirrigated treatment. Irrigation generally increased total and marketable fruit yield, increased the average fruit weight and reduced green fruit yield and blossom-end rot when compared with the unirrigated treatment. Percent fruit solids were reduced, but total solid yields (t ha-1) were increased by irrigation. In a dry year (2005), fruit and total solid yields increased with irrigation water level but were not affected by the preharvest water cutoff time. In wetter years, the irrigation regime that applied the least water (0.5 ETc) reduced the amount of water applied to the crop while maintaining high yields and fruit quality. Fruit maturity, colour, firmness and the amount of culled fruit were not influenced by either the irrigation water level or the preharvest water cutoff time. The irrigation regime that applied the least water when used in combination with an early preharvest water cutoff appeared to counteract the reduction in percent fruit solids associated with irrigation. Some reduction in yield may occur with this irrigation regime and rainfall may interfere with implementation of this strategy. Key words: Lycopersicon esculentum, yield, blossom-end rot
A re-evaluation of crop heat units in the maritime provinces of Canada
Authors: Bootsma A. , McKenney D. W. , Anderson D. , Papadopol P.
Published: April 2011

Crop heat units (CHU) are commonly used to rate suitability of corn (Zea mays L.) hybrids and soybean [Glycine max (L.) Merrill] varieties for production in various regions of Canada. The CHU map presently in use for the Maritime provinces is based on climate data from the period 1956 to 1985. This paper presents an updated CHU map for the region using the latest available climate normals (1971 to 2000) and up-to-date interpolation and mapping procedures. Decadal time trends of CHU and water deficits are also examined for seven selected climate stations in the region. Average CHU ratings often increased by 100 units or more for the most recent period, with some exceptions. Station decadal trends from 1955 to 2004 confirmed the warming trend, with an average increase of 86 CHU per decade. Increased CHU have promoted higher potential yields in corn and soybean in the region, although this potential was not likely met during the last decade due to frequent droughts in some areas. However, there is presently little evidence to suggest that higher yield potential will be significantly limited by changing water deficits as a re sult of greenhouse-gas induced global warming in this century. Key words: Corn, Zea mays, soybean, Glycine max, climate trends, yield, water deficits