bluuebunny/crossref_metadata_2025 huggingface dataset:
Root maggots (Delia spp., Diptera: Anthomyiidae) in prairie canola (Brassica napus L. and B. rapa L.): Spatial and temporal surveys of root damage and prediction of damage levels
Authors: Soroka J. J. , Dosdall L. M. , Olfert O. O. , Seidle E.
Published: April 2011

The levels of infestation and damage to canola taproots caused by crucifer-feeding root maggots (Delia spp.)(Diptera: Anthomyiidae) were determined through surveys of commercial crops across the canola growing regions of western Canada. Canola root damage caused by Delia spp. maggots was measured at the end of the season by determining the percentage of plants infested (PPI) per field and estimating average damage levels (DL, on a scale of 0 to 5) to taproots. Over the course of the survey, 2890 canola fields were sampled. Infestation by root maggots occurred wherever canola is grown in western Canada. In the study, 96% of the fields surveyed in Manitoba and Saskatchewan and 99.8% of the fields in Alberta showed evidence of root maggot feeding, with PPI much higher than in provincial surveys of a decade previously. Geographical ecoregion significantly affected both PPI and DL. The greatest amount of damage over the largest area was found in western and northwestern Alberta, although localized areas with severely damaged roots occurred along the northern edge of the entire Parkland ecoregion. Over the entire survey area, Brassica rapa L. roots had greater PPI and DL than B. napus L. roots, although species differences were not significant in Saskatchewan or Manitoba. Data from the survey were correlated with weather variables to develop a model predicting the levels of damage inflicted by root maggots to canola roots. Of the weather variables investigated, temperature, especially the average temperature in the preceding July and August, had the greatest in fluence on PPI and DL. The warmer the temperatures of the preceding July and August, the lower the PPI and DL in the current year. Likewise, previous year’s July and August precipitation influenced PPI and DL negatively. Other weather parameters had little consistent influence on PPI and DI. The predictive model for PPI and DL, developed from the 1995–1998 survey data, incorporated canola species, ecoregion, previous July-August and September-October temperatures and precipitation. The validity of the model was assessed using a set of survey data collected in Alberta from 1981 to 1983. Regression equations of predicted results on actual results were significant. However, r2 values for the regressions were low, in part because of the few ecoregions surveyed and the lack of canola species data recorded in the earlier survey, and because of the large increase in infestation levels since the earlier data were collected. The study is a first step in forecasting the effects of root maggots across a wide geographic area featuring many different canola production practices. Key words: Crucifer-feeding root maggots, Delia spp., canola, Brassica rapa, Brassica napus, pest forecasting, distribution of damage
The biology of Canadian weeds. 130. Amaranthus retroflexus L., A. powellii S. Watson and A. hybridus L.
Authors: Costea M. , Weaver S. E. , Tardif F. J.
Published: April 2011

A review of the biological information published after 1980 is provided for three species of the genus Amaranthus: A. retroflexus L., A. powellii S. Watson and A. hybridus L. The three species are noxious weeds introduced to Canada from southern North America. Their geographical distribution has remained almost unchanged since the original paper published in 1980. The plants exhibit a high phenotypic plasticity and genetic variability and they easily adapt to a multitude of agrestal and ruderal habitats. The seeds contribute to a persistent seed bank; they exhibit a variable dormancy and polymorph germination as a result of maternal, genetic and environmental factors. Growth is rapid and plants produce a large number of viable seeds. The three species have developed multiple resistance to triazine and acetolactate-synthase-inhibiting herbicides. They are alternate hosts to many insects, nematodes, viruses, bacteria and fungi that affect cultivated plants. Key words: Amaranthus retroflexus, Amaranthus powellii, Amaranthus hybridus, weed biology, ecology, taxonomy, herbicide resistance
Tolerance of cranberry beans (Phaseolus vulgaris) to soil applications of s-metolachlor and imazethapyr
Authors: Soltani N. , Shropshire C. , Cowan T. , Sikkema P.
Published: April 2011

There is little information on the tolerance of cranberry beans to preplant incorporated (PPI) and preemergence (PRE) applications of s-metolachlor and imazethapyr, eithe r alone or in tank mix combination, for selective weed control in cranberry beans in Ontario. Tolerance of two cranberry bean cultivars, Hooter and SVM Taylor, to PPI and PRE applications of s-metolachlor, imazethapyr and their tank mix combination at the label rate (1×) and twice the label rate (2× ) were studied at two Ontario locations (Exeter and Ridgetown) in 2001 and 2002. There were no differences between the two cultivars in their responses to the herbicide treatments. PPI and PRE applications of s-metolachlor alone at the 1× and 2× rate had no effect on visual crop injury and no negative effect on plant height, dry weight and yield compared to the control. The PPI and PRE applications of imazethapyr at the 1× rate did not result in significant visual crop injury, and had no negative effect on bean height and dry weight, but at the 2× rate there was significant visual crop injury, a decrease in height with the PPI application and decreased dry weight with PPI and PRE applications. No negative effect o n cranberry bean yield was observed with the application of imazethapyr at either the 1× or 2× rates. The PPI and PRE applications of the tank mix of s-metolachlor plus imazethapyr at the 1× rate did not result in significant visual crop injury or decreases in bean plant height or dry weight. At the 2× rate, there was significant visual crop injury, a decrease in bean plant height with PPI and PRE applications and decreased dry weight with the PPI application. The tank mix of s-metolachlor plus imazethapyr at the 1× rate had no effect on yield, but the PPI application at the 2× rate caused a decrease in yield at 1 of the 4 site-years. Key words:
Assessing resistance to spring black stem and leaf spot of alfalfa caused by Phoma spp.
Authors: Wang H. , Hwang S. F. , Chang K. F. , Gossen B. D. , Turnbull G. D. , Howard R. J.
Published: April 2011

The disease reaction of alfalfa (Medicago sativa) cultivars to spring black stem was evaluated in field trials and greenhouse experiments. In field trials, differences in cultivar reaction to leaf spot (predominantly spring black stem) were observed in 9 of 16 station years. The reaction of certain cultivars was consistent across most trials, but other cultivars were quite variable. Under controlled conditions, one isolate each of Phoma sclerotioides and P. exigua produced symptoms on alfalfa leaves that were similar to those caused by P. medicaginis. These results indicate that P. medicaginis is not the only pathogen responsible for symptoms of spring black stem on alfalfa in the prairie region. In a detached-leaf study, one isolate each of P. medicaginis, P. sclerotioides and P. exigua produced leaf lesions on all 18 alfalfa cultivars assessed. Disease incidence in Absolute, Algonquin, Pickseed 3006 and Anik (M. sativa subsp. falcata) was lower than in 630 and AC Blue J. Inoculation of eight selected cultivars using a range of spore concentrations under controlled conditions showed a similar pattern; all three isolates produced leaf lesions on all eight cultivars. Ino culation with conidial suspensions of P. medicaginis resulted in a lower disease incidence on Absolute than on Beaver. Key words: Medicago sativa, Medicago sativa subsp. falcata, Phoma medicaginis, P. sclerotioides, P. exigua, detached leaves.
CDC Anna desi chickpea
Authors: Vandenberg A. , Warkentin T. , Slinkard A.
Published: April 2011

CDC Anna, a desi chickpea (Cicer arietinum L.) cultivar, was released in 2000 by the Crop Development Centre, University of Saskatchewan for distribution to Select seed growers in western Canada through the Variety Release Committee of the Saskatchewan Pulse Growers. CDC Anna has a pinnate leaf type, fair ascochyta blight [Ascochyta rabiei (Pass.) Labr.] resistance, medium maturity, medium-sized plump seeds with a tan coloured seed coat and good yielding ability in the Brown and Dark Brown soil zones of the Canadian prairies. Key words: Chickpea, Cicer arietinum L., cultivar description, ascochyta blight
Fatty acid and elemental composition of mature seeds of beach pea [Lathyrus maritimus (L.) Bigel.]
Authors: Arya Kumar Bal Gurusamy Chinnasamy, , McKenzie David Bruce
Published: April 2011

This study was conducted to determine the fatty acid composition of phospholipids (PL), monoglycerides (MG), diglycerides (DG), free fatty acids (FFA) and triglycerides (TG) of mature beach pea seeds and the elemental composition of mature beach pea seed coats and embryos. In beach pea seeds, PL were dominated by C18:2 and C16:0 and MG contained high quantities of C18:2, C16:0 and C18:1. Diglycerides showed high C18:0, C16:0 and C18:2. Free fatty acids were dominated by C18:2, C16:0, C18:1 and C18:0, and TG were dominated by C18:1, C18:0 and C16:0. Energy dispersive X-ray microanalysis revealed K as the most abundant element in whole seed, seed coat and embryo. However, embryos showed significantly higher relative weight percentage of K than whole seeds and seed coats. Whole seeds and embryos contained higher P, S and Cl relative weight percentages than seed coats. Seed coats contained higher Ca, Na a nd Mg relative weight percentages than embryos. Aluminium, Si, Mn, Fe, Cu and Zn distribution between seed coat and embryo was uniform. Key words: Beach pea, element, fatty acid, Lathyrus maritimus L., lipid, seed
A novel source of resistance to verticillium wilt in alfalfa
Authors: Gossen B. D. , Jefferson P. G.
Published: April 2011

Verticillium wilt (VW) can cause substantial losses in yield and stand longevity in alfalfa. Resistant cultivars are available, but susceptible cultivars continue to be grown on the Canadian Prairies, where VW generally occurs only under irrigation. A study was conducted to assess the yield and persistence of 11 alfalfa lines under irrigation on three commercial fields in southern Saskatchewan. An epidemic of verticillium wilt developed at one site; the disease reaction of the susceptible Medicago sativa ssp. falcata line ‘SC Mf3713’ was similar to that of the resistant cv. Barrier. SC Mf3713 may carry a novel form of field resistance to VW, and merits further study. Key words: Medicago sativa ssp. falcata, Verticillium albo-atrum
Nitrate and pesticide leaching from a processing carrot production system in Nova Scotia
Authors: Gordon R. , Elmi A. A. , Madani A. , Hauser T. , Rodd V. , Leblanc P.
Published: April 2011

Environmental concerns associated with the continuous application of manure on farmland include potential contamination of surface and subsurface aquatic ecosystems. Our objective was to explore the potential environmental impact of utilizing liquid hog manure (LHM) as a fertilizer in carrot (Daucus carota L.) production. The effects of LHM (169 kg N ha-1; 50% assumed to be available), inorganic fertilizer (IF) (NPK; 70-80-100 kg ha-1) treatments and herbicide (linuron) application on the quality of drainage water from a carrot production system in Nova Scotia were examined. Nitrate-N (NO3−-N) (1 mg NO3−-N L-1 ≈ 4.5 NO3− L-1) concentrations resulting from two applications of 70 t ha-1 of LHM and 70 kg N ha-1 as ammonium nitrate (34-0-0) applied to tile-drained plots were monitored over 2 yr. The average NO3−-N concentrations in the drainage discharge were slightly greater for the LHM treatment (14.4 mg L-1) compared to the IF treatment (12.9 mg L-1), but the difference was not statistically significant (P > 0.05). Most drainage and NO3−-N losses occurred outside the growing season (November-April), but average NO3−-N concentrations in the drainage discharge exceeded 10 mg L-1 both during and outside the growing season. Flow rates of drainage discharge were not significantly affected by the fertility treatments. Less than 0.1% of the linuron herbicide applied to the test plots leached into the drainage water over the study period. Carrot yields were unaffected by the fertility treatments. We conclude that LHM is potentially useful source of nutrients for carrot with minimal harm to the environment, under the rates and management practices used in this study. However, excessive rates of application and/or long-term (>10 yr) repeated applications of manure may negatively impact water quality. Key words: Daucus carota, amendment, leaching, manure, yield
Nordbec barley
Authors: Ho K. M. , Choo T. M. , Rowsell J. , Guillemettte L. , Scheifele G. , Martin R. A.
Published: April 2011

Nordbec is an early-maturing, six-rowed, spring feed barley (Hordeum vulgare L.) cultivar developed by the Eastern Canada Barley Breeding Group, Agriculture and Agri-Food Canada. It has high yield, improved straw strength and resistance to powdery mildew. Nordbec is suitable for production in northern Ontario. Key words: Cultivar description, Hordeum vulgare L., early maturity, feed barley, high yield, short straw
ACE-1 perennial cereal rye
Authors: Acharya S. N. , Mir Z. , Moyer J. R.
Published: April 2011

ACE-1 perennial cereal rye (PC rye) (Secale cereale) was developed by the Agriculture and Agri-Food Canada Research Centre, Lethbridge, Alberta. This cultivar, tested as LRC 96-1 in western Canada, was developed for silage and greenfeed. ACE-1 is easy to establish, competes well with weeds, grows early in spring, produces more biomass than barley and fall rye under dryland and irrigated conditions, but produces less seed than high yielding fall rye cultivars. Forage quality of ACE-1 was found to be similar to barley. Key words: Cultivar description, rye, perennial, Secale cereale
Long-term effect of cropping system and nitrogen and phosphorus fertilizer on production and nitrogen economy of grain crops in a Brown Chernozem
Authors: Campbell C. A. , Zentner R. P. , Selles F. , Jefferson P. G. , McConkey B. G. , Lemke R. , Blomert B. J.
Published: April 2011

Assessment of the long-term impact of fertilizers and other management factors on crop production and environmental sustainability of cropping systems in the semi-arid Canadian prairies is needed. This paper discusses the long-term influence of N and P fertilizers on crop production, N uptake and water use of hard red spring wheat (Triticum aestivum L.), and the effect of the preceding crop type [flax (Linum usitatissimum L.) and fall rye (Secale cereale L.)] on wheat grown on a medium-textured, Orthic Brown Chernozem at Swift Current, Saskatchewan. We analysed 36 yr of results (1967–2002) from eight crop rotation-fertility treatments: viz., fallow-wheat receiving N and P (F-W, N + P), three F-W-W treatments fertilized with (i) N + P, (ii) P only, and (iii) N only; two other 3-yr mixed rotations with N + P (i) F-flax-W (F-Flx-W) and (ii) F-fall rye-W (F-Rye-W); and two continuous wheat rotations (Cont W), one receiving N + P and the other only P. Growing season weather conditions during the 36-yr period were near the long-term mean, but the first 22 yr were generally drier than normal while the last 14 yr (1989–2002) had average to above-average growing conditions. This was partly responsible for grain and N yield being greater in the latter period than in the first 22 yr. The 36-yr average response of wheat grown on fallow to P fertilizer was 339 kg ha-1, while the response to N fertilizer over this period was only 123 kg ha-1. The 36-yr average response of wheat grown on stubble to N was 344 kg ha-1 for F-W-(W) and 393 kg ha-1 for Cont W. Neither flax nor fall rye influenced the yield response of the following wheat crops. Annualized grain production for F-W (N + P), F-W-W (+ N) and F-W-W (+ P) rotations were similar (1130 kg ha-1 yr-1); this was about 15% lower than for F-W-W (N + P), 40% lower than for Cont W (N + P), and 5% lower than for Cont W (+ P). Annualized aboveground N yield for Cont W (N + P) was 57% higher than for Cont W (+ P). Regressions were developed relating straw to grain yields for wheat, flax and fall rye. The amount of NO3-N left in the soil was directly related to amount of N applied and inversely to N removed in the crop. Thus, F-(W)-W (+ N) left about 28% more NO3-N in the rooting zone than F-(W)-W (N + P), while F-W-(W) (N + P) left 20% more than F-W-(W) (+ P), and Cont W (N + P) left 39% more than Cont W (+ P). F-Rye-W (N + P) left much less NO3-N in the soil than any other fallow-containing system and similar amounts to Cont W (N + P). Key words: Yields, grain protein, N and P fertilizer, straw/grain regressions, water use, soil nitrate
Seed quality response of soybean to weed control timing using glyphosate
Authors: Essah S. Y. C. , Bishnoi U. R.
Published: April 2011

Field and laboratory studies were conducted during 1997 and 1998 in the southeast United States to determine the influence of timing of glyphosate application on seed germination (standard germination and germination index) and vigor (cold test emergence, accelerated aged emergence, and seed conductivity) of three glyphosate-resistant soybean [Glycine max (L.) Merr.] cultivars that belong to different maturity groups (MG). The soybean cultivars used were H4994 (MG IV — early maturing), H5164 (MG V — medium maturing) and H6686 (MG VI — late maturing). Weeds were controlled by glyphosate applied at 1.1 kg a.i. ha-1 at 2, 3, 4, 5, 6, or 7 wk after soybean emergence (WAE). Using glyphosate to control weeds at 5 WAE or later in the early- and medium-maturing cultivars (H4994 and H5164) results in soybean plants able to produce seeds with more vigor and germinability than when weeds are removed earlier. For late-maturing cultivar H6686, weed control at 4 WAE produces seeds with higher germination and vigor than when weeds are removed later. Key words: Glyphosate, weed control timing, soybean, seed germination and vigor, weed dry weight
The effect of nitrogen and boron fertilizer applications on Willamette red raspberry growth, and on applied and other nutrients in the plant and soil over two growing seasons
Authors: Kowalenko C. G.
Published: April 2011

The effects of three single, spring fertilizer treatments (complete, complete minus N and complete minus B) on raspberry plants were examined in detail over two seasons. Phosphorus, K, Ca, Mg, Na, Cu, Mn, Fe, Zn in addition to N and B were measured in various plant parts and soil samples monthly. There were no fertilizer effects on berry yield, but treatment-year primocane stem and residualyear floricane stems and laterals were smaller without N. Minus B reduced application-year lateral weights. Soil nitrate concentrations were consistently low without N showing plants used soil organic N as it was mineralized. Soil nitrate concentrations were greater with than without N during the first growing season only. Above-ground plant uptake of the 134 kg N ha-1 application was 34% over the 2 yr. Leaf tissue concentrations were too dynamic for plant N status evaluation, but floricane stem N concentrations showed promise. Hot water extract B in soil responded to B application, but varied with time of sampling. Significant soil B remained in the soil into the second year, apparently not leached as readily as nitrate. Leaf B concentrations were too variable over time for plant B status evaluation, but floricane laterals showed promise. The treatments influenced concentrations of elements other than N and B, but only above-ground P and Mn accumulations were affected significantly. Detailed plant and soil analyses were necessary to fully evaluate treatment effects on this complex-growing perennial crop. Key words: Raspberry yield, raspberry N accumulation, raspberry B accumulation, raspberry nutrient dynamics, apparent N recovery, apparent B recovery, soil nitrate test, nitrate leaching, soil extractable B, residual effects
Fall vs. spring rhizobial inoculation of chickpea
Authors: Kyei-Boahen S. , Giroux C. , Walley F. L.
Published: April 2011

Field experiments were conducted in Saskatchewan using chickpea (Cicer arietinum L.) to evaluate fall-applied granular rhizobial inoculant. Seed yield and percentage N derived from fixation generally did not differ between granular inoculant applied in the fall (FG) and seed applied peat-based powder (SP). Results suggest that FG applications may be an alternative to spring seed inoculation for chickpea. Key words: Chickpea, rhizobial inoculant, granular inoculant, nodulation, N2 fixation
A bimodal model for oat kernel size distributions
Authors: Doehlert D. C. , McMullen M. S. , Jannink J. L. , Panigrahi S. , Gu H. , Riveland N. R.
Published: April 2011

Oat kernel size distributions are important to the oat milling industry because size separation of kernels is routine in oat milling. Dehuller rotor speeds are set in order to deliver the optimal mechanical stress to different kernel size streams for dehulling. In this study, size distributions were evaluated by digital image analysis in 10 cultivars grown in eight environments. Observed distributions were compared with quality characteristics and with panicle characteristics and spikelet type frequencies. Size distributions within samples, as evaluated from individual kernel image areas, tended to depart from normal distributions and graphical depictions of data frequently resembled bimodal populations. A statistical test to compare a bimodal distribution with a normal distribution indicated that a bimodal model was more effective at describing the distributions. Panicle analysis indicated that two-kernel spikelets were the most abundant spikelet type found. Because two-kernel spikelets consist of one larger kernel and one smaller kernel, it is likely that the root of the bimodal distribution can be attributed to these spikelets. Although some departures from the mixture of two normal distributions can be attributed to the occurrence of one- and three-kernel spikelets, many of these departures must be attributed to other sources of variation in oat kernel size. Key words: Oats, panicle, kernel size, spikelets
Phosphorus fertilization and asparagus yield during establishment years
Authors: Sommerville D. W. , Whalen J. K.
Published: April 2011

Adequate P is important for the production of healthy asparagus (Asparagus officinalis L.) plants. This study determined how varying P fertilization rates affected asparagus yields obtained 3 and 4 yr after planting 1-yr-old crowns. The P fertilizers were applied annually at 0, 50, 75 100 and 200% of the recommended rate for Québec. The recommended rates for P fertilizer are much higher in the year that the crowns are planted than in a producing asparagus field as the goal at planting is to establish soil fertility levels that will sustain production for 15 yr or longer. Marketable yields for the various P fertility regimes ranged from 2060 to 2460 kg fresh weight (FW) ha-1 in the first year of harvest and between 3015 and 3250 kg FW ha-1 in the second year. Marketable yields were not affected by P fertilization in either year, suggesting unamended soil at the test site contained adequate P (about 160 mg Mehlich III extractable P kg-1) for asparagus production. The rates of P removal in the harvested asparagus spears were low compared to fertilizer P applications. All of the P fertilizer rates applied increased the Mehlich III extractable P concentration and the P saturation ratio of the soil above critical agroenvironmental limits. Further study is needed to develop P fertilizer recommendations that maintain asparagus yields and quality without contributing to environmental pollution. Key words: Mehlich III-extractable P, P nutrient management, P saturation
Effects of wounding and inoculation with Sclerotinia sclerotiorum on isoflavone concentrations in soybean
Authors: Wegulo Stephen N. , Yang Xiao-Bing , Martinson Charlie A. , Murphy Patricia A.
Published: April 2011

Isoflavones play an important role in the defense response of soybean to pathogen attack. They are involved in nodulation of legumes and are associated with human health benefits including the prevention of heart disease and cancers. Concentrations of the isoflavones daidzein, genistein, and glycitein, the glucoside conjugates daidzin, genistin and glycitin, the acetylglucoside conjugates acetyldaidzin, acetylgenistin, and acetylglycitin, and the malonylglucoside conjugates malonyldaidzin, malonylgenistin, and malonylglycitin were determined in ovendried leaves of 12 soybean cultivars whose stems were (i) non-wounded, non-inoculated (NWNI), (ii) wounded, non-inoculated (WNI), and (iii) wounded and inoculated (WI) with mycelia of Sclerotinia sclerotiorum, the causal fungus of Sclerotinia stem rot of soybean. There were significant differences (P ≤ 0.05) among cultivars in concentrations of isoflavones and their conjugates in all wounding treatments. Concentrations of the aglycones daidzein and genistein were higher (P ≤ 0.05) in WI than in WNI and NWNI plants in all cultivars. Glycitein and its conjugates were detected only in some cultivars in much lower concentrations than daidzein and genistein and their conjugates. Concentrations of total daidzein in the 12 cultivars ranged from 68 to 491, 174 to 781, and 282 to 553 µg g-1 dry weight in NWNI, WNI, and WI plants, respectively. Concentrations of total genistein ranged from 128 to 427, 290 to 840, and 296 to 759 µg g-1 dry weight in NWNI, WNI, and WI plants, respectively. Concentrations of total glycitein ranged from 0 to 44, 0 to 13, and 0 to 24 µg g-1 dry weight in NWNI, WNI, and WI plants, respectively. In NWNI plants, the cultivar Corsoy 79 ranked in the top two (rank 1 = highest concentration, rank 12 = lowest concentration) in concentrations of daidzein and genistein and their conjugates except genistin (ninth rank). In WNI plants, Parker ranked first in concentrations of all conjugates of daidzein and genistein whereas Corsoy 79 consistently ranked in the top four in concentrations of the two isoflavones and their conjugates. In WI plants, Parker ranked first in concentrations of all conjugates of daidzein and genistein except acetyldaidzin (second rank), S19-90 ranked in the top five in concentrations of all conjugates of daidzein and genistein, whereas Corsoy 79 ranked in the top five in concentrations of daidzein and genistein and all of their conjugates. The results from this study suggest that soybean cultivars differ in concentrations of constitutive or induced isoflavones and in their ability to accumulate isoflavones following wounding and/or infection by S. sclerotiorum. Key words: Isoflavones, soybean, leaves, Sclerotinia sclerotiorum, wounding, HPLC
RCAT Wildcat soybean
Authors: Stirling B. T. , Fischer J. D. , Zhao G. , Ablett G. R.
Published: April 2011

RCAT Wildcat is a 2950 crop heat unit (CHU) soybean [Glycine max (L.) Merrill] cultivar with excellent yield potential, good lodging resistance and above-average seed protein levels. It was developed by the Ridgetown College, University of Guelph, and is adapted to the 2800–3100 CHU areas of Ontario. RCAT Wildcat was issued registration number 5568 on 2002 Dec. 11 by the Variety Registration Office, Plant Production Division of the Canadian Food Inspection Agency. Key words: Soybean, cultivar description
Effect of post-emergence nitrogen application on the yield and protein content of wheat
Authors: Karamanos R. E. , Flore N. A. , Harapiak J. T.
Published: April 2011

Post-emergence application of N with wheat is contemplated as a practice for managing risk and reducing fertilizer N costs. An attempt was made to develop a comprehensive agronomic package relating to the practice of post-emergence applications by examining aspects relating to the rates of N, timing of post-emergence applications and products that might be used for that purpose. An extensive database of 49 trials conducted between 1995 and 1998 separated in five experimental plans was utilized to address the above issues. Nitrogen rates of up to 100 kg N ha-1 were employed as soil applied at seeding by side banding (0, 20, 40 and 60 kg N ha-1) plus topdressed (0, 20 and 40 kg ha-1) as post-emergence applications between Feekes growth stages 10.4 and 10.5. The effect of timing was explored in three different experimental designs that included rates up to 100 kg ha-1 applied at seeding or split, so that a post-emergence application of 20 kg N ha-1 was applied at Feekes growth stages 10 and 10.5, or up to 60 kg N ha-1, applied either all at seeding time or 20 or 40 kg N ha-1 at seeding time accompanied by 20 or 40 kg N ha-1 in a post-emergence application at Feekes growth stages 3–4, 6, 10.5 or 11. A number of products (ammonium nitrate, ammonium sulphate, urea, urea ammonium nitrate, Pro N and N serve) were also evaluated for their effectiveness in post-emergence applications. Two distinct trends emerged from all experiments depending on whether application of N at seeding corrected an N deficiency. If N deficiency was corrected by the application rate at seeding then the post-emergence N application increased grain protein concentrations; however, this practice was shown to result in no economic advantage. If N deficiency was not corrected by the N application at seeding, post-emergence applications at late growth stages increased grain protein of wheat at the expense of grain yield. This increase was greater in soils containing soil organic matter (SOM) concentrations less than 5% than those over 5%. Increases in grain protein ranged from 0.7 to 1.5% depending on initial fertilization regime, but they were not sufficient in any of the circumstances to economically compensate for the loss in grain yield caused by insufficient application of N at seeding. The performance of a number of products used for post-emergence application on the protein of hard red spring wheat was mixed with none proving to be consistently superior. Post-emergence application of N to enhance either the grain yield or protein of hard red spring wheat could be effective under high moisture or irrigated conditions; however, this practice represents a relatively high-risk practice under dryland conditions in the western Canadian prairies. Key words: Economics, growth stage, N rates, N products, timing
Relationships and inheritance of linolenic acid and seed lipoxygenases in soybean crosses designed to combine these traits
Authors: Reinprecht Yarmilla , Rajcan Istvan , Poysa Vaino W , Ablett Gary R , Pauls K Peter
Published: April 2011

To improve oxidative stability of soybean oil and reduce off-flavours, we previously developed low linolenic acid, lipoxygenase-free (LLA.3lx) soybean germplasm. The objectives of this study were to characterize the patterns of inheritance and determine the relationships between the low linolenic acid (LLA) trait derived from the lines RG10 and PI 361088B and seed lipoxygenase nulls (3lx) from a triple null line OX948 that were used to create the new LLA.3lx germplasm. Reciprocal crosses between RG10 and OX948 and between PI 361088B and OX948 were made and populations derived from them were evaluated for their fatty acid profiles and seed lipoxygenases (LX) at the F2, F5 and F6 generations. Both RG10 and PI 361088B contain a single gene that controls linolenic acid (LA) content with alleles acting in an additive manner. No significant cytoplasmic effects were observed on LA content. The LLA trait was highly heritable in both RG10 × OX948 (RO) and PI 361088B × OX948 (PO) crosses and stable in different environments (Belize and Ontario, Canada). The three seed LX were each controlled by single genes, but lipoxygenase 1 (Lx1) and lipoxygenase 2 (Lx2) were tightly linked. No significant correlations were observed between LA content and seed LX. The simple and independent inheritance of LA and seed LX in these crosses should simplify breeding for soybean cultivars that are resistant to oxidative degradation. Key words: Soybean, linolenic acid, lipoxygenase, inheritance, trait relationships
Plasticity, life cycle and interference potential of field violet (Viola arvensis Murr.) in direct-seeded wheat and canola in central Alberta
Authors: Degenhardt Rory F. , Spaner D. , Harker K. Neil , Raatz Lisa L. , Hall Linda M.
Published: April 2011

Field violet is an established weed of field crops in Europe and eastern North America. It has recently been identified in field crops of central Alberta. Natural infestations of field violet in direct-seeded wheat and canola in central Alberta were observed in 2002 and 2003. Field violet exhibited summer annual, winter annual and short-lived perennial life cycles. Plants emerged in variable flushes, with peaks in early-June and September. Very few annuals produced seed during the season if they emerged after June, but some (< 45%) of these plants successfully overwintered. Summer annuals began dispersing mature seed 7 wk after emergence, but were also capable of persisting in a quiescent state for extended periods (up to 19 wk). Wheat and canola yield loss attributable to field violet was minimal. We compared domestic and European field violet accessions to determine if the study population represented a unique agroecotype. Plants from both cohorts grown in the greenhouse were near-identical, suggesting that differences resulted from phenotypic plasticity, rather than genetic divergence. Field violet appears to be well adapted to growing conditions and farming practices in Alberta, but is a poor competitor and is unlikely to cause serious crop production losses. Key words: Environmentally regulated plasticity, field violet, Viola arvensis, weed emergence, weed phenology
PRO 30-05 Soybean
Authors: Fischer J. D. , Stirling B. T. , Zhao G. , Ablett G. R.
Published: April 2011

PRO 30-05 is a 3050 crop heat unit (CHU) soybean [Glycine max (L.) Merrill] cultivar with excellent yield potential, good lodging resistance and above-average seed protein levels. It was developed by the Ridgetown College, University of Guelph, and is adapted to the 2900-3250 CHU areas of Ontario. Key words: Soybean, cultivar description
Effect of fall and spring seeding on canola productivity in the Peace River region of northern Alberta
Authors: O’Donovan John T , Otani Jennifer , Clayton George W , Soon Yoong K
Published: April 2011

The feasibility of dormant seeding canola in the fall in the Peace River region of northern Alberta was assessed. Results indicated that there is a significant risk of crop failure with fall seeding, mainly due to poor spring seedling emergence. Where a fall-seeded canola crop established, flowering and seed maturity occurred earlier even though plant densities were lower with fall compared with spring seeding, and seeding date had little or no effect on canola seed yield or quality. Tillage (minimum or zero) or nitrogen rate, source or placement had no consistent effects on canola productivity. Canola growers in the Peace River region are unlikely to achieve higher yield and quality by seeding canola in the fall. Key words: Dormant seeding, fertilizer rate, source and placement, minimum and zero tillage, polymer coated canola seed
Effects of heavy grazing pressure on the random amplified polymorphic DNA marker diversity of mountain rough fescue (Festuca campestris Rydb.) in south western Alberta
Authors: Mengli Z. , Willms W. D. , Bing H. , Laroche A.
Published: April 2011

The Fescue Grassland is found in the western portion of the Northern Great Plains in Canada. Grazing and cultivation threaten this grassland, and a better understanding of its character is needed to preserve its integrity. Mountain rough fescue is highly sensitive to grazing during the growing season, which results in smaller plants and the death of some. The death of plants suggests the potential loss of genetic diversity. Therefore, we compared the genetic diversity of mountain rough fescue plants from sites in south western Alberta (50°12′N, 113°54′W) that had either been heavily grazed by livestock or left ungrazed for 52 yr to determine if grazing pressure had affected their genetic composition. Thirty-four and 43 plants were sampled in the spring of 2001 from very heavily grazed and ungrazed subpopulations, respectively, and their DNA was analyzed using random amplified polymorphic DNA (RAPD). Of the 15 primers used, 12 generated an average of seven polymorphic loci each. Ten loci were present at a frequency of 0.10 or less in the heavily grazed subpopulation and six in the ungrazed subpopulation. RAPD marker diversity between the heavily grazed and ungrazed subpopulations of mountain rough fescue was mainly the result of frequency differences (P < 0.05) produced by 20% of the total markers that were examined, while the subpopulations accounted for only 4.37% of total heterozygosity. Therefore, grazing affected frequency of some markers but did not eliminate genes that may be linked with grazing sensitivity or tolerance. Lack of clear genetic segregation between the subpopulations might be caused by a high gene flow (Nm = 10.92). This mechanism requires further testing in order to prescribe a suitable management response for restoring overgrazed grasslands. Key words: RAPD frequency, F-statistics, genetic identity, genetic distance, gene flow
Fructooligosaccharides changes during maturation in inflorescences and seeds of onion (Allium cepa L. ‘W202’)
Authors: Shiomi N. , Benkeblia N. , Onodera S. , Kawazoe N.
Published: April 2011

The distribution of fructooligosaccharides (FOS) and their related enzyme activities during the development of the inflorescences and the maturation of seeds in onion (Allium cepa L.) were investigated. Concentrations of glucose, fructose and sucrose in three inflorescence parts – complete floral parts (FP), pedicels (PD) and involucres (IV) - increased steadily during the first 8 wk of sampling and then decreased over for the next 6 wk. However the final glucose, fructose and sucrose contents were not significantly higher than those observed at the beginning of sampling. Surprisingly, FOS concentration in the inflorescence parts for the saccharides studied showed similar patterns with concentrations increasing during the first 6 wk and decreasing during the last 6 wk of the study. On the other hand, FL and PD parts contained higher amounts of FOS than IV parts. The activities of sucrose:sucrose 1-fructosyltransferase (SST), fructan: fructan 6G-fructosyltransferase (6G-FFT) and fructan:fructan 1F-fructosyltransferase (1-FFT) showed similar patterns in seeds, decreasing slowly during the first weeks and remaining stable thereafter. The ratio 6G-FFT to 1-FFT decreased after 9 wk from 2.40 to 1.44 with an average of 2.1. In contrast, activities of invertase and β-fructofuranosidase increased progressively, although β -fructofuranosidase activity was twice as high as invertase activity during the last 2 wk. The ratio of synthesizing to hydrolysing activities decreased progressively to 0.2 and was below the value 1 after 9 wk. Thus, it seems that seed maturation was reached during the last week of August, which is 2 to 3 wk earlier than seed harvest normally occurs in Hokkaido. Key words: Fructooligosaccharides, flower organs, seeds, onion
Managing nitrogen fertility of irrigated soft white spring wheats for optimum quality
Authors: Guttieri Mary J. , Cecile Becker Katherine O’Brien, , Stark Jeffrey C. , Windes Juliet , Souza Edward
Published: April 2011

Irrigated wheat growers often choose to apply only part of the crop’s nitrogen fertilizer requirement at planting to avoid over-fertilizing the crop at early stages of growth. Later in the growing season, producers will apply additional nitrogen fertilizer as needed to optimize production. This study evaluated effects of top-dress nitrogen fertilizer application timing and rate on the milling and baking quality of two soft white spring wheat cultivars produced in an irrigated environment when the pre-plant fertility rates were insufficient for optimal crop yield. Top-dress N increased lactic acid solvent retention capacity (SRC), a measure of gluten strength, of the resulting flour by increasing flour protein concentration. Although lactic acid SRC response and the grain yield response to top-dress fertilizer were unaffected by application timing, other quality parameters, including break flour yield, flour ash, and, in the case of the cultivar Alturas, sugar snap cookie diameter, were affected by application timing. Earlier timing of top-dress fertilization minimized the detrimental effects of the fertilizer application on break flour yield and flour ash concentration. Key words: Soft wheat, nitrogen, gluten, flour ash
Agronomic and environmental factors influence weed composition and canola competitiveness in southern Manitoba
Authors: Bullied W. J. , Van Acker R. C. , Marginet A. M. , Kenkel N. C.
Published: April 2011

Canola yield in Manitoba has reached a plateau in recent years. The causes for this, as related to agronomic, environmental, weed interference and canola competitiveness factors, were identified using observational data from 31 canola fields in southern Manitoba in a 2-yr on-farm research study. Agronomic and environmental factors contributing to weed density and composition were determined with multivariate canonical correspondence analysis. Agronomic and environmental factors most influential on absolute and relative canola biomass were determined with multiple regression analysis. Most weeds were adaptable across a broad range of crop environments; however, some functional groups of weeds were either positively or negatively favored by specific environmental or agronomic conditions. Absolute canola biomass prior to bolting was greater as soil growing degree days (GDD) increased and canola was dense and seeded early. Lower weed density, increased soil GDD, and reduced surface soil moisture were significant factors contributing to higher relative canola biomass. Results from this study indicate that seeding canola early and at a rate sufficient to achieve a dense crop stand can increase canola competitiveness and reduce weed interference. Key words: Agronomy, canola, competitiveness, environment, weeds
Cultivar and fertilizer S rate interaction effects on canola yield, seed quality and S uptake
Authors: Malhi S. S. , Gill K. S
Published: April 2011

Since canola has a high requirement for S, and canola cultivars have differences in growth rate and yield potential, a differential response of canola cultivars to soil S deficiency and S fertilization can be expected. A 3 site-year field study was conducted on S-deficient soils in northeastern Saskatchewan to determine response of four canola cultivars to S deficiency and S fertilization in terms of yield (seed and straw), seed quality (oil, protein and S concentration), and S uptake (seed and straw). Two Brassica napus L. cultivars (Quantum and AC Excel) and two B. rapa L. cultivars (Maverick and AC Parkland) were compared at 0, 5, 10, and 15 kg S ha-1 rates. Both the actual values of seed and straw yield and seed S uptake and the responses to S fertilization were greater for the B. napus than B. rapa cultivars. Optimal yield response for all the four cultivars occurred at the 10 kg S ha-1 rate, though seed quality and S uptake responded up to the 15 kg S ha-1 rate. Sulphur fertilization response was quadratic for seed and straw yield, seed oil and protein concentration, and S uptake in seed, while the response for seed S concentration and straw S uptake was inconsistent. In summary, in spite of differences in magnitude of the response of tested cultivars to S fertilization, the similar nature of the response and optimal yield at the same S rate indicated th at specific S fertilization recommendations for individual canola cultivars are unnecessary. Key words: Canola cultivars, oil concentration, seed quality, S rates, S uptake, yield
The yield potential of winter wheat established in a dry seedbed and at different seeding depths
Authors: Lafond G. P. , May W. E. , Irvine B.
Published: April 2011

The growth habit of winter wheat offers unique benefits in prairie cropping systems. Successful production requires early seeding, usually into a dry seed bed. Seeding date and seeding depth effects were investigated under three very contrasting weather scenarios. Risk in dry years on the Canadian prairies was reduced when winter wheat was seeded shallow (<25 mm) and early (beginning of September). Key words: Triticum aestivum L., fall climatic conditions, establishment, plant stand
Interspecific differentiation and phylogenetic relationships of poison ryegrass (Lolium temulentum L.) and Persian darnel (L. persicum Boiss. & Hohen. ex Boiss.)
Authors: Senda T. , Ohsako T. , Tominaga T.
Published: April 2011

To clarify the speciation and evolution of the inbreeding Lolium spp., poison ryegrass and Persian darnel, we analyzed genetic relationships using microsatellite and AFLP markers among accessions from Pakistan, where both species grow sympatrically or parapatrically. Dendrograms were constructed using the unweighted pair-group method with arithmetic averages (UPGMA), based on simple matching coefficient of similarity among 29 accessions of poison ryegrass and 16 accessions of Persian darnel. Most of the poison ryegrass and Persian darnel accessions were genetically divided into two clusters. One and two chloroplast RFLP (restriction fragment length polymorphism) haplotypes were identified in poison ryegrass and Persian darnel accessions, respectively, from Pakistan, which correspond to each cluster or subcluster of dendrograms. Some accessions, morphologically identified as Persian darnel, belong to neither poison ryegrass nor Persian darnel clusters and locate in other cluster between them. Because this intermediate group had the same haplotype as poison ryegrass, shared almost all alleles with poison ryegrass and/or Persian darnel, and was genetically closer to poison ryegrass than to Persian darnel, we hypothesize that the intermediate group was derived maternally from poison ryegrass via hybridization with Persian darnel. Key words: AFLP, chloroplast DNA-RFLP, Lolium persicum, Lolium temulentum, microsatellite, phylogenetic analysis
Lodging increases severity and impact of mycosphaerella blight on field pea
Authors: Wang T. F. , Gossen B. D. , Slinkard A. E.
Published: April 2011

Mycosphaerella blight, caused by Mycosphaerella pinodes, is a serious disease of pea (Pisum sativum) world-wide. The objective of this study was to assess the impact of lodging (reduced lodging treatment vs. control) and foliar fungicide (three to four applications of chlorothalonil vs. control) on the severity of mycosphaerella blight, and on seed yield and 1000-seed weight of 10 pea genotypes (three adapted cultivars and seven genotypes with partial resistance). In the reduced lodging treatment, a wire mesh was secured 30 cm above the ground; the crop was allowed to grow up through the mesh and be supported by it. The study was conducted under irrigation at two locations in Saskatchewan for 2 yr. Blight severity on stems, foliage, and pods was rated three to four times per year. The reduced-lodging treatment and application of fungicide reduced blight severity and increased seed yield and 1000-seed weight. The effects of reduced lodging and fungicide application were additive. Overall, lodging was associated with the largest reductions in seed yield and seed weight, but the impact of fungicide application was slightly larger than that of lodging for the three commercial cultivars. We conclude that losses caused by mycosphaerella blight may be reduced by breeding for improved resistance to lodging, but that application of foliar fungicide and breeding for partial resistance also hold promise. Key words: Pisum sativum, Mycosphaerella pinodes, resistance, fungicide, yield loss, quality