Ultra-early seeding provides several benefits for hexaploid wheat (Triticum aestivum L.), including an extended planting window, grain yield protection, enhancement and stability, earlier harvest, and improved weed competitiveness. However, a knowledge gap exists around whether durum wheat (Triticum turgidum ssp. durum) is also amenable to this practice. Thus, an experiment was conducted at four locations in Alberta and Saskatchewan, Canada, from 2022 to 2024. The treatment combinations consisted of five durum wheat cultivars, planted at six soil temperature triggers separated by 2 degrees C increments beginning at 0 degrees C through to 10 degrees C. Among the cultivars, irrespective of planting time, AAC Donlow, CDC Defy, and AAC Stronghold attained similar grain yields when averaged across all environments, which were superior to CDC Desire and Transcend. Planting at a soil temperature of 2 degrees C measured at the 5-cm soil depth generally resulted in higher grain yields and greater net returns. Moreover, a partial least squares regression-additive Main effects and multiplicative interaction analysis indicated that a 2 degrees C planting system was better adapted to warmer June and arid summer conditions, which suggests the system imparts enhanced heat and drought stress resilience. If planting was delayed-that is, >= 10 degrees C soil temperature-a yield drag was usually experienced. Grain protein concentration was not affected by the soil temperature trigger. Thus, commercially available durum cultivars are amenable to ultra-early seeding and optimized when planted at a soil temperature of 2 degrees C, which could increase returns by $CAD 134 ha(-1). Future studies will investigate durum responses when planted ultra-early versus dormant-plantings in fall, with variations to planting depth.

In the context of canola (Brassica napus L.)-winter wheat (Triticum aestivum L.) rotational systems, the timing of canola stubble availability and effective weed management play a crucial role in the production of a subsequent winter wheat phase. This study, conducted from 2018 to 2022 across the Canadian prairies, applied a genotype x environment x management framework to examine how manipulations to canola harvest management can help optimize winter wheat production. The factorial treatment structure included two canola hybrids (early- and late-maturing), three canola harvest management systems (early-timing and conventional windrowing at 40 % and 60 % seed color change, respectively, and straight-cutting at 10 % seed moisture), and three weed management treatments (pre-harvest herbicide for canola, pre-plant herbicide for winter wheat, and pre-harvest+pre-plant herbicides). Windrowing and pre-harvest herbicides were completed simultaneously by retrofitting the swather with an onboard sprayer. Across all 16 site-years, winter wheat planted after a late-maturing canola hybrid demonstrated comparable performance to that after early-maturing canola. However, delaying canola harvest reduced winter wheat yields. Conventional windrowing in conjunction with pre-harvest herbicide or preharvest+pre-plant herbicides improved winter wheat yields and enhanced weed management, while maintaining canola seed quality, as no herbicide residues were detected in the harvested seed. Our previous research indicated that in-crop herbicide applications are unnecessary due to the high competitiveness of winter wheat against weeds. This research reaffirms in-crop herbicides could be eliminated and underscores the competitiveness and sustainability that a winter wheat phase offers when integrated in Canadian Prairie cropping systems.

The production of barley cultivars with malting and brewing quality characteristics is subject to strict grading and technical standards for the end-use market. Environmental and management factors can significantly alter grain quality, and the qualities required for malting. Crop and kernel uniformity are critical factors where variability can exceed the tolerance for meeting malt quality. A practice to address variations in crop maturity is the application of pre-harvest glyphosate. Pre-harvest glyphosate applications can, however, alter malting characteristics in barley, and, if mis-timed, can also reduce yield. A 4-year study at five locations in Alberta and Saskatchewan from 2013 to 2017 was conducted to determine the effects of pre-harvest glyphosate applications on malting barley characteristics. Glyphosate was applied at 900 and 1125 g ae ha −1 on malting barley cultivars ‘CDC Meredith’ and ‘AC Metcalfe’ malting barley at soft dough, hard dough, and physiological maturity growth stages. Yield reductions of up to 12% were observed from glyphosate applications at soft dough, and yield was maximized with applications at physiological maturity. Glyphosate application, at two rates, reduced percentage plump kernels, but did not affect kernel weight or protein concentration. The growth stage of barley plants did not provide an accurate indicator of seed moisture levels at the time of application, which motivated our conclusion that glyphosate applications can be mistimed by inaccurate indicators. The results motivate our questioning of the utility of pre-harvest glyphosate applications, given the adverse effects to barley yield and quality observed, even when applied according to the label instructions.

Winter wheat production in Canada is approximately 5% of all the wheat seeded in Canada; however, it has important economic and agronomic benefits for growers. Stripe rust of wheat, caused by Puccinia striiformis f. sp. tritici Eriks. occurs across western Canada in many years; as a result, it is prudent to evaluate strategies to control stripe rust in winter wheat. The objective of this project was to evaluate the effects of fall and spring fungicide application (metconazole and pyraclostrobin) on stripe rust, as well as leaf spot severity, and impact on yield and quality of winter wheat (Triticum aestivum L.). The effect of fungicide application in the fall, in the spring, or both, on four winter wheat cultivars varying in resistance to these diseases was evaluated at 11 site-years in Alberta and Saskatchewan for four growing seasons from 2013 to 2017. Stripe rust severity on the susceptible cultivars, 'AC Bellatrix' and 'CDC Osprey', and leaf spot severity on these cultivars and 'Radiant', was reduced by single spring or dual (fall and spring) applications, but not by fall application alone when disease severity was high. Single spring and dual fungicide applications to 'AC Bellatrix' maintained yield potential by 16.9-229.5% compared to the unsprayed treatment. Grain quality was also maintained by the same treatments at some site-years. During the study, virulence of the natural Pst population on 'Radiant' with the Yr10 resistance gene was differentially expressed among sites and therefore yield response to fungicide varied. The stripe rust resistant cultivar 'Moats' did not benefit from fungicide application at any timing. Single fall fungicide application had no effect on disease severity of any of the cultivars at any site-years, although it had minor effects on yield or grain quality of 'AC Bellatrix' at a few site-years. Multiple fungicide applications, in fall and again in spring, did not offer additional benefits to a single spring application.

Malting barley is important in western Canada, yet many malting cultivars do not meet malt quality standards, in part due to lodging. Lodging can decrease barley yield and quality thereby reducing the acceptability for malting. In other countries, plant growth regulator (PGR) applications are used to mitigate lodging. Chlormequat chloride (chlormequat), trinexapac-ethyl (trinexapac), and ethephon were tested at five locations over 3 yr in western Canada for their ability to limit lodging, as well as their effects on yield, agronomic traits, and pre-malt quality characteristics. PGR applications occurred between Zadoks growth stage (GS) 30–33 for chlormequat and trinexapac and GS 37–49 for ethephon. Seeding rates of 200, 300, and 400 seeds m−2 of CDC Copeland barley were used to increase the likelihood of lodging. Increased seeding rate decreased tillers per plant, height, days to maturity, kernel protein, and kernel weight. Ethephon increased the number of tillers per plant and decreased plant height, kernel plumpness, and kernel weight. Trinexapac decreased plant height and kernel weight. Days to maturity was investigated across site-years, with ethephon increasing maturity in 60% of comparisons. Trinexapac and chlormequat had limited effects on maturity. Lodging was investigated across site-years, with trinexapac showing the largest number of lodging reductions and scale of reductions. Ethephon reduced lodging in 36% of comparisons, while chlormequat had inconsistent effects. None of the products affected yield or grain protein. The results suggest PGRs may not be the solution to lodging for CDC Copeland barley on the Canadian Prairies; however, trinexapac shows the most promise of the products tested.

Currently, no in-crop herbicide is registered to control wild oat (Avena fatua L.) in tame oat (Avena sativa L.). Wild oat must be controlled in tame oat using other agronomic practices. The objective of this research was to determine if side-banded phosphorus (P) in combination with seeding rate would increase the competitiveness of tame oat with wild oat, increasing yield and quality. An experiment was conducted from 2003–2005 at Indian Head, SK. The experimental design was a strip-plot design with four replications. The strips were low and high wild oat density. A two-way factorial, seeding rate (150, 250, 350, and 450 plants m−2), and P rate (0, 15, and 30 kg P2O5 ha−1) were seeded across the strips. Phosphorus affected seed density, grain yield, oat biomass, and wild oat fecundity. Seeding rate affected most of the measured variables and interacted with wild oat and year. The application of P increased the competiveness of oat by increasing crop biomass by 7.6% and grain yield by 3.4% and decreasing wild oat seed from 1.26% to 0.76% in the harvested grain. Wild oat decreased grain yield by 23% in 2003, 4.4% in 2004, and 11% in 2005. Increasing the seeding rate increased grain yield by 5% when wild oat was present. Wild oat did not interfere with the uptake of side-banded P. Producers need to use both P fertilization and higher seeding rates to improve the competitiveness of tame oat and the management of wild oat in tame oat.

A 6-yr study was conducted across western Canada to evaluate the residual eff ects of preceding crops (PCs) and past N rate management on the economics of subsequent wheat (Triticum aestivum L.) and canola (Brassica napus L.). Field pea (Pisum sativum L.), lentil (Lens culinaris Medik.), canola and wheat harvested for grain, and faba bean (Vicia faba L.) grown and harvested for grain or as a green manure were direct seeded in 2009. Canola was seeded in 2010, barley in 2011, and canola again in 2012 with fertilizer N applied at varying rates for each crop. Spring wheat grown in 2013 and canola in 2014, both without N application, were used to determine residual PC and residual N eff ects. Th e positive benefi t of legume PCs on the annual crop net revenue (NR) of wheat and canola crops diminished over time. Residual N from previously applied N had positive eff ects on annual wheat NR in 2013, but only the highest application rate contributed signifi cantly to canola NR in 2014. Th e NR was greatest with an annual fertilization program based on regional production capacity, but under the dry conditions of the Canadian prairies excess N remaining in the soil aft er crop production could remain in the soil as residual N to be used by following crops. While generally insuffi cient to optimize crop production, residual N can reduce the economic risk from over-application of fertilizer if N is not utilized by the crop due to adverse growing conditions in the year of fertilizer application.

In the past, most sunflower research was conducted in tilled cropping systems and was based on wide row configurations established using precision planters. Little agronomic information is available for the no-till systems predominant in Saskatchewan, where crops are typically seeded in narrow rows using an air drill. Two studies were conducted in Saskatchewan to determine the optimum seeding and nitrogen (N) rates for short-season sunflowers in a no-till cropping system. The N rate study used 5 N rates (10, 30, 50, 70, and 90 kg N ha−1) with the hybrid 63A21. The seeding rate study used 7 seeding rates (37 000, 49 000, 61 000, 74 000, 86 000, 98 000, and 111 000 seeds ha−1) with two cultivars, AC Sierra (open pollinated) and 63A21 (hybrid). There was a linear yield increase as the N rate increased from 10 to 90 kg N ha−1. Based on the N rates tested in this study and current N fertilizer costs below $1 kg−1, sunflower yields and gross returns were most favorable at 90 kg N ha−1. Future N response research with a wider range of N rates is warranted to best determine the optimum N rate. The optimum seeding rate was between 98 000 and 111 000 seeds ha−1 for AC Sierra and between 74 000 and 86 000 seeds ha−1 for 63A21. The optimum plant density, approximately 70 000 to 75 000 plants ha−1, was similar for both cultivars. These results are higher than the current recommended seeding rates for wide-row precision planting systems in areas with a longer growing season.

Leaf spotting diseases commonly occur on spring wheat crops grown in Saskatchewan, causing yield losses of up to 15%, although greater losses have been documented during severe epidemics. In the past decade, Fusarium head blight (FHB) has become a major concern for growers resulting in extensive use of fungicide to mitigate the disease. The optimal fungicide timing for leaf spot control is generally at the flag-leaf stage, while the optimal timing for FHB is during anthesis. The objective of this study was to determine whether applying fungicide at anthesis timing can provide adequate control of leaf spots when compared to application at flag-leaf stage. Fungicide treatments applied at flag-leaf, anthesis, and both growth stages were evaluated on the cv. Carberry. Prothioconazole + tebuconazole and tebuconazole (only) applied at anthesis provided adequate control of leaf spots, although the severity of leaf diseases was slightly higher in this treatment than application at flag-leaf stage but yields were similar. Test weight and thousand kernel weight were improved with the application at anthesis relative to that at flag-leaf stage. Two applications of fungicide provided only a small incremental benefit to the anthesis application, and would not be economically justified in western Canada at this time. Anthesis fungicide application provided adequate leaf spot disease control and is the optimum timing for the control of FHB.

A western Canada field study investigated the effects of seeding date and rate on malting barley quality. Seeding date had little effect on quality. Increasing the seeding rate up to 300 seeds m(-2) resulted in higher germination and Kolbach indices, lower beta-glucan, and better endosperm modification without compromising malt extract.

Profitable malting barley (Hordeum vulgare L.) production systems are required to reverse the decline in area seeded to malting barley in western Canada. Systems that could increase the profitability of growing malting barley considered the previous crop, nitrogen (N) rate, and fungicide application. The net return (NR) and risk for these systems were computed from western Canada field data. Analysis of variance was used to evaluate the impact of systems on NR over 21 site-years of field data. Risk was evaluated with a stochastic simulation model. NR was higher and risk lower for malting barley when the preceding crop was field pea (Pisum sativum L.), when fungicide was applied at the flag leaf stage for leaf disease control, and when N was 50% of the recommended N rate. Therefore, malting barley should be grown on field pea stubble at a lower N rate, with fungicide applied when there are leaf diseases.

There is interest in mixing herbicides with a half-rate of fungicide at herbicide timings for barley in western Canada. At six sites across the Canadian prairies from 2010 to 2012 combinations of herbicide and the fungicide Tilt (R) (propiconazole) were applied to barley at the two-to three-leaf stage (herbicide and half-rate fungicide), five-to six-leaf stage (herbicide and half-rate fungicide), and/or the flag leaf stage (full or half-rate fungicide only). Each plot area was cross-seeded with tame oat as a model weed prior to seeding. Upper canopy leaf samples were collected for leaf disease assessment at the early dough growth stage. Weed biomass, and grain yield and quality were determined. Total leaf area diseased (a combination of scald, both forms of net blotch and spot blotch) was greater for the two-to three-or five-to six-leaf stage herbicide-only treatments and the combination herbicide and half-rate fungicide treatments compared with fungicide at the flag leaf stage. Yield, 1000-kernel weight, kernel plumpness and test weight were greatest and kernel thins lowest for treatments with a flag leaf stage fungicide application. Split applications of fungicide at the time of herbicide application and at flag leaf emergence did not improve disease management and crop productivity compared with a single full rate fungicide application at the flag leaf stage. Weed biomass was generally not influenced by the treatments because weed control was excellent at all sites. However, yield was lower when herbicide was applied at the five-to six-leaf versus the two-to three-leaf stage. For improved leaf disease management and yield in barley, fungicide applications should include a flag leaf stage timing for adequate protection of upper canopy leaves, which are key contributors to yield and grain filling. Delaying herbicide application to the five-to six-leaf stage in an attempt to accommodate a fungicide application reduces barley yield due to early-season weed interference.

O'Donovan, J. T., Anbessa, Y., Grant, C. A., Macleod, A. L., Edney, M. J., Izydorczyk, M. S., Turkington, T. K., Juskiw, P. E., Lafond, G. P., May, W. E., Harker, K. N., Johnson, E. N., Beres, B. L., McAllister, T. A., Smith, E. G. and Chapman, W. 2015. Relative responses of new malting barley cultivars to increasing nitrogen rates in western Canada. Can. J. Plant Sci. 95: 831–839. Only about 25% of barley (Hordeum vulgare L.) is selected for malting annually in western Canada due to quality issues. While nitrogen (N) fertilization can increase yield, it can also impair quality by increasing protein to unacceptable levels. The objective of this study was to determine the responses of relatively new malting barley cultivars (Bentley, Major, CDC Meredith, and Merit 57) to increasing N rates compared to the response of AC Metcalfe, the most commonly grown malting cultivar. Experiments were conducted at seven locations in western Canada in 2010, 2011 and 2012. Nitrogen was banded at seeding at 0, 30, 60, 90, or 120 kg ha−1. All the new varieties produced higher yield (5 to 11%) than AC Metcalfe. Barley kernel yield and protein concentration increased with N rate. However, Merit 57, CDC Meredith and Bentley produced significantly lower protein concentration in response to N than AC Metcalfe and Major. The newer cultivars displayed higher N utilization efficiency than AC Metcalfe, possibly due to partitioning proportionally more N into leaf chlorophyll development. The higher leaf chlorophyll content may have enabled increased photosynthesis and a more efficient utilization of N for grain formation. Bentley produced the least tillers and had the highest kernel plumpness, while Merit 57 had the lowest kernel plumpness. CDC Meredith lodged most followed by Merit 57, while Major and Bentley lodged least, especially at the higher N rates. Merit 57 and CDC Meredith took longer to mature than the other cultivars but yielded well at relatively short growing season locations.

May, W. E., Ames, N., Irvine, R. B., Kutcher, H. R., Lafond, G. P. and Shirtliffe, S. J. 2014. Are fungicide applications to control crown rust of oat beneficial? Can. J. Plant Sci. 94: 911–922. Crown rust (Puccinia coronata Corda f. sp. avenae Eriks.) negatively impacts seed quality and yield in oat (Avena sativa L.) in rust-prone areas of eastern Saskatchewan, Manitoba, Ontario, and Quebec. Genetic resistance is the primary means for controlling this disease, but early seeding and fungicide applications have been suggested to reduce yield losses. Trials were conducted in six locations in Saskatchewan and Manitoba in 2009–2011 to determine the interactions between cultivar, fungicide application, crown rust and seeding date. The cultivars were chosen to represent a range of resistance to the current races of crown rust: AC Morgan, very susceptible; CDC Orrin, susceptible; CDC Boyer, partially resistant; and Leggett, resistant. Crown rust severity varied among locations and cultivars. The sprayed flag and penultimate leaves of AC Morgan tended to have similar amounts of crown rust as the unsprayed leaves of CDC Boyer and CDC Orrin regardless of the level of crown rust infection. Leggett's yield and quality did not respond to fungicide application. Only AC Morgan consistently benefited from a fungicide application. At high crown rust sites fungicide application improved AC Morgan's yield by 17 to 27% (690 kg ha−1 to 781 kg ha−1). Delayed seeding reduced grain yield from 8 to 26% with 8% occurring at low crown rust sites and the largest reductions occurring at high crown rust sites in susceptible cultivars. The test weight of AC Morgan increased from 242 g 0.5 L−1 to 255 g 0.5 L−1 when fungicide was applied at high crown rust sites seeded in mid-May. Fungicide application did not change the test weight of Leggett. The β-glucan level was affected more by seeding date (0.4%) and cultivar (0.4%) than fungicide application (0.1%). Seeding a cultivar with better crown rust resistance than AC Morgan in mid-May eliminated most of the benefits derived from fungicide application. These results indicate that prophylactic fungicide applications are unlikely to provide yield improvement when early planting is combined with even a moderately disease-resistant cultivar.

Fernandez, M. R., May, W. E., Chalmers, S., Savard, M. E. and Singh, A. K. 2014. Are early foliar fungicide applications on durum wheat grown in southeast Saskatchewan beneficial in increasing grain productivity? Can. J. Plant. Sci. 94: 891–903. Producers have expressed interest in applying fungicides early in the development of durum wheat to reduce disease severity and increase grain yield. To address this issue, a field trial was conducted in southeast Saskatchewan (2004–2006) to determine the impacts of single and double foliar fungicide (tebuconazole) applications at various growth stages on leaf spotting, Fusarium head blight/Fusarium-damaged kernels, deoxynivalenol concentration, dark kernel discolouration, and grain traits of durum wheat. In most cases, application at stem elongation was not effective in reducing Fusarium diseases, or improving yield and grain characteristics. Application at flag leaf emergence was more effective, but for the most part, application at anthesis resulted in the most consistent reduction in disease levels, and improvement in test weight. Double fungicide applications (stem elongation or flag leaf emergence, and anthesis) were not more effective in disease control than a single application at anthesis. Grain yield did not differ significantly among any of the treatments. In contrast to Fusarium diseases and leaf spotting, fungicide applications at stem elongation and/or flag leaf emergence resulted in increased kernel weight and percentage dark kernel discolouration, which was significant in 2005 (10.53–10.60% total kernel discolouration in the stem and flag leaf treatments vs. 6.13% for the untreated control). In one or more years, kernel weight was negatively associated with Fusarium disease variables and leaf spotting, but positively associated with kernel discolouration. We conclude that under variable environmental conditions in Saskatchewan, early preventative fungicide use on durum wheat should not be recommended as a strategy to improve productivity, and might even result in increases in dark kernel discolouration and grain downgrading.

May, W. E., Johnson, E. N., Sapsford, K. L., Stevenson, F. C., Lafond, G. P., Holzapfel, C. B. and Holm, F. A. 2014. Tolerance of annual canarygrass (Phalaris canariensis L.) to combinations of MCPA, clopyralid, fluroxypyr and florasulam. Can. J. Plant Sci. 94: 701–708. Annual canarygrass (Phalaris canariensis L.) is a cereal crop that is primarily grown on the Canadian prairies as feed for caged birds. To widen the spectrum of herbicide options for producers, two experiments were conducted with the following nine herbicide treatments (application rates in parentheses expressed as g a.i. ha−1): weed-free control; single and double applications of MCPA (560)+clopyralid (100) (Curtail M); MCPA (562)+fluroxypyr (108) (Trophy); and MCPA (560)+clopyralid (100)+fluroxypyr (144) (Prestige); florasulam (5)+MCPA (420) (Frontline); difenzoquat (700)+MCPA (560)+clopyralid (100) (Avenge+Curtail M); and a single application of difenzoquat (700). Experiment 2 included the same herbicide treatments in factorial combinations with two application times; crop growth stages of two to three leaf (2–3 lf) and four to five leaf (4–5 lf). Experiments were conducted at Indian Head, Scott, and Saskatoon, SK, in 2001 to 2003. In exp. 1, difenzoquat caused up to 30% crop injury when combined with MCPA+clopyralid at the 2× rate, but improved crop yield relative to other herbicides because it reduced yield interference from wild oat infestations at Indian Head in 2002. In exp. 2, the 2× rate of florasulam+MCPA resulted in the greatest visual injury, with higher levels recorded at the 2–3 lf; however, seed yield reduction was greater when applied at the 4–5 lf. In summary, annual canarygrass was tolerant to combinations of MCPA, clopyralid, and fluroxypyr, herbicides which control important weed species in prairie fields.

Camelina [Camelina sativa (L.) Crantz] is a new crop to western Canada, and research information on its response to nitrogen fertilizer is lacking. Two field experiments were conducted from 2008 to 2010 in Saskatchewan and Alberta, Canada, to determine the effect of N fertilizer application on camelina plant establishment, seed and straw yield, total N uptake in seed and straw, seed oil and protein concentration, N fertilizer use efficiency (NFUE) and percent recovery of applied N (%NR) in seed. Nitrogen fertilizer rates ranged from 0 to 160 kg N ha(-1) in exp. 1 and from 0 to 200 kg N ha(-1) in exp. 2. There was generally no detrimental effect of high N rates on plant establishment, with the exception of 1 site-year in which there was a slight linear decline in plant density as N rate increased. Seed yield, total N uptake in seed, NFUE and %NR responded to applied N rates at most site-years. Seed yield and total N uptake in seed usually increased while seed NFUE and %NR decreased with increasing N rate. Response trends of yield and total N uptake of straw to applied N were similar to that of seed at the corresponding site-years. Seed oil concentration decreased while protein concentration increased with increasing N rate. In exp. 1, fertilizer rates were not high enough to attain a maximum seed yield; however, maximum seed yields of 2013 kg ha(-1) were achieved at an N rate of 170 kg N ha(-1) in exp. 2. In conclusion, camelina responded to fairly high rates of applied N similar to responses reported for Brassica juncea on the Canadian prairies.

Irvine, B. R., Lafond, G. P., May, W., Kutcher, H. R., Clayton, G. W., Harker, K. N., Turkington, T. K. and Beres, B. L. 2013. Stubble options for winter wheat in the Black soil zone of western Canada. Can. J. Plant Sci. 93: 261-270. Winter wheat (Triticum aestivum L.) production has yet to reach its full potential in the Canadian prairies. Alternative stubble types are needed to help overcome the challenge of timely planting of winter wheat in late-maturing canola (Brassica napus L.) fields. A study was conducted in the prairie provinces of Canada to determine ideal stubble types for winter wheat and select spring cereals grown in the Black soil zone. Spring wheat (Triticum aestivum L.), canola, pea (Pisum sativum L.), barley grain or silage (Hordeum vulgare L.), and oat (Avena sativa L.) stubbles were established at four locations in western Canada. A new study area was established at each location for 3 yr. In the year following establishment, winter wheat, hard red spring wheat, barley, and oats were grown on each stubble type at each study area. Winter wheat and spring cereal crops often yielded best and had greater grain protein concentration on barley silage, pea, and canola stubbles relative to other stubble types. The yield and grain protein concentration of spring cereals was best when grown on pea stubble. Winter wheat production attributes varied most among site by crop combinations, and further investigation indicated the source of this variability may be from winter wheat plantings on canola and pea stubble. Among the optimal stubbles, less variable results were observed when winter wheat was grown on barley silage stubble, suggesting proper crop residue management would reduce the variability observed in canola and pea stubble. Our results suggest stubble alternatives to canola are available for winter wheat plantings in western Canada.

May, W. E., Fernandez, M. R., Selles, F. and Lafond G. P. 2014. Agronomic practices to reduce leaf spotting and Fusarium kernel infections in durum wheat on the Canadian prairies. Can. J. Plant Sci. 94: 141–152. Fusarium head blight (FHB) has become an important disease of durum wheat [Triticum turgidum L. ssp. durum (Desf.) Husn] in the humid and sub-humid regions of the prairies along with leaf spots, black point and red smudge. Together, they contribute to lower grain yields and grain quality. The study objective was to determine the effect of seeding rate, nitrogen (N) fertilizer rate, fungicidal treatment, and cultivar on disease severity, crop development, grain yield and quality in durum. A four-way factorial design was used with two seeding rates (150 and 300 viable seeds m−2), two N rates (75 and 100% of recommended rate), three cultivars (AC Avonlea, AC Morse and AC Navigator), four fungicide treatments (no application, propiconazole at flag leaf, tebuconazole at anthesis, and propiconazole at flag leaf followed by tebuconazole at anthesis) and three locations (two in Saskatchewan and one in Manitoba) from 2001 to 2003. There were no interactions among fungicide, seeding rate, N fertilizer and cultivar for all measured variables. Foliar fungicide treatments resulted in greater kernel weight, grain yield and test weight than the no-fungicide treatment. The application of tebuconazole at anthesis did not reduce the amount of FDK in the harvested grain. The application of a fungicide increased the percentage of kernels infected by black point from 0.38% to over 0.50% and red smudge from 0.54 to 0.61%. Two fungicide applications increased red smudge to 0.85%. Grain yield increased by 2.4% when the seeding rate was increased from 150 to 300 plants m−2. Increasing N fertilizer rate increased grain yield by 5.2%, protein concentration by 5.4% and hard vitreous kernels (HVK) by 2.6%, but decreased test weight by 0.5%. Cultivar selection had the largest effect on FDK. In conclusion, effects of a fungicide application on durum wheat did not interact with selection of seeding rates, cultivars or N rates used in this study.