In response to concerns about acetolactate synthase (ALS) inhibitor-resistant weeds in wheat production systems, we explored the efficacy of managing Bromus spp., downy and Japanese bromes, in a winter wheat system using alternative herbicide treatments applied in either fall or spring. Trials were established at Lethbridge and Kipp, Alberta, and Scott, Saskatchewan, Canada over three growing seasons (2012)(2013)(2014) to compare the efficacy of pyroxasulfone (a soil-applied very-long-chain fatty acid elongase inhibitor; WSSA Group 15) and flumioxazin (a protoporphyrinogen oxidase inhibitor; WSSA Group 14) against industry-standard ALSinhibiting herbicides for downy and Japanese brome control. Winter wheat injury from herbicide application was minor, with the exception of flucarbazone application at Scott. Bromus spp. control was greatest with pyroxsulam and all herbicide treatments containing pyroxasulfone. Downy and Japanese bromes were controlled least by thiencarbazone and flumioxazin, respectively, whereas Bromus spp. had intermediate responses to the other herbicides tested. Herbicides applied in fall resulted in reduced winter wheat yield relative to the spring applications. Overall, pyroxasulfone or pyroxsulam provided the most efficacious Bromus spp. control compared with the other herbicides and consistently maintained optimal winter wheat yields. Therefore, pyroxasulfone could facilitate management of Bromus spp. resistant to ALS inhibitors in winter wheat in the southern growing regions of western Canada. Improved weed control and delayed herbicide resistance may be achieved when pyroxasulfone is applied in combination with flumioxazin.

It is unknown if winter pea (Pisum sativum L.) and winter lentil (Lens culinaris Medik.) are feasible cropping options in Alberta. Field experiments were conducted at six locations in southern and central Alberta, Canada, between 2008 and 2012, to determine the adaptability of winter pea and lentil. Two winter pea cultivars, Specter and Windham, and one winter lentil cultivar, Morton, were seeded at three fall planting dates and three seeding rates. Spring cultivars were grown for comparison. In southern Alberta, winter pea and lentil yielded up to 39% more than spring types. The highest winter pea yield was achieved when planting was completed during the first 3 wk of September. The highest winter lentil yield was achieved when planting was completed in the second and third weeks of September. Seeding rate had little or no impact on yield; therefore, winter pea should be seeded at 75 plants m−2 and winter lentil at 110 plants m−2. Seed was analyzed to compare constituent parameters. There were minor differences in the composition of winter and spring pulses. Windham had lower starch but higher resistant starch, protein, crude fat, and ash content compared with spring pea cultivars. Specter had higher resistant starch but was similar to Cutlass for all other parameters. Morton had a higher starch content than CDC Redberry; however, starch quality was similar. Winter pulses have potential to create new and profitable opportunities for growers in the Bow Island and Lethbridge areas of southern Alberta.

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Hailstorms can be responsible for significant economic loss to the agricultural sector in Alberta, Canada. Foliar applications of certain fungicides and nutrient blends have been advocated to promote recovery and yield of hail-damaged crops. Proper understanding of different crop and hail-related factors is required for an accurate assessment of hail damage to crops, and for evaluations of hail-recovery product claims. This study was undertaken at three locations in Alberta during three growing seasons (2016-18) to determine the effects of two levels of simulated hail severity at three different crop developmental stages including early growth (BBCH 30 for wheat; BBCH 14-16 for pulses), mid-growth (BBCH 39 for wheat; BBCH 60 for pulses) and late growth (BBCH 60 for wheat; BBCH 71 for pulses) stages. Plant growth, and yield parameters of wheat (Triticum aestivum L.), field pea (Pisum sativum L.) and dry bean (Phaseolus vulgaris L.) crops were measured. Simulated hail damage led to reductions in height, biomass, NDVI, grain yield and kernel weight of all three crops. Average yield decreased by 24 and 35% for wheat, 17 and 35% for dry beans, and 37 and 45% for field peas for light and heavy hail severity, respectively. Hail timing was a critical factor influencing the extent of crop damage, with hail damage during early growth stage leading to lesser yield reduction compared to hail damage at mid-growth and late growth stages. Fungicides and nutrient blends applications did not significantly improve crop recovery, grain yield or kernel weight for any of the crops in this study.

Optimizing the timing of nitrogen (N) enhanced efficiency fertilizers (EEFs) may maximize winter wheat (Triticum aestivum L.) grain yield, protein content, and N-use efficiency (NUE). From 2013 to 2018, experiments were conducted at two irrigated and six rain-fed sites across the Canadian Prairies (24 site-years) to evaluate winter wheat responses to N source and timing/placement effects of EEFs. Nitrogen sources included untreated urea, nitrification inhibitor nitrapyrin treated urea (Nitrapyrin), urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) plus nitrification inhibitor dicyandiamide (DCD) treated urea (NBPT+DCD), and polymer-coated urea (PCU). The N sources were all side-banded at planting, 30% side-banded at planting plus 70% broadcast in-crop late-fall (averaged 38 days after planting; split-applied late-fall) or 30% side-banded at planting plus 70% broadcast in-crop early-spring (averaged 224 days after planting; split-applied early-spring). Nitrous oxide and methane emissions were measured at one rain-fed site to test whether N source and timing/placement influenced CO2-equivalents (CO2-eq; nitrous oxide+methane). Under irrigation, NBPT+DCD consistently produced the highest yields regardless of timing/placement; however, the 80% of recommended rate caused sub-optimal protein responses (≤11%) unless split-application of N was adopted. . Untreated urea produced the highest net CO2-eq and yield-scaled CO2-eq emissions, with the highest emissions when urea was split-applied early-spring. To optimize winter wheat production and NUE, we conclude that NBPT+DCD all-banded during seeding operations or split-applied early-spring provided similar and often superior results than other sources including a more typical system of urea side-banded at the time of seeding.