Precision planters are recently being adopted for seeding canola to improve crop establishment and seed yield. This study determined the effect of seeding canola using precision planters (30.5 and 50.8 cm seeding row width) and conventional air drill seeders at different rates (20, 40, 60, 80 and 160 seeds m-2) on plant density and seed yield. The study was conducted for four years (2016 to 2019) at three locations in southern Alberta. Plant density increased with higher seeding rates following the negative exponential function distribution. The yield-density relationship was non-linear asymptotic in nature and weak-to-moderate in strength at most site-years. The parameters of yield-density relationship did not show statistically significant differences among the air drill and precision planters. When averaged among seeding rates, canola yield was higher for the narrow row precision planter at five site-years and for the air drill at two site-years out of a total of 12 site-years. Under irrigated and high-precipitation conditions, seed yield in narrow-row precision planted canola was higher than air drill seeded canola. There was an average increase of 463 kg ha-1 (10%) in the seed yield in narrow-row precision planted canola compared to the air drill seeded canola among irrigated systems. However, under water-limited conditions, seed yield in air drill seeded canola was comparable or higher than the precision planted canola. Wide-row planter led to poor crop establishment and seed yield under both irrigated and dryland conditions, attributed to higher in-row plant density due to wider row spacing.

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.