Irrigated short-season soybean production in Southern Alberta: Optimizing row spacing, seeding density and nitrogen fixation

Abstract

Soybean [Glycine max (L.) Merrill] has expanded into southern Alberta. The study was at Bow Island and Lethbridge in Year 1 (2014, 2015), Year 2 (2015, 2016). A first experiment included: soybean (Co-op - F045R #3, G1; NSC Tilston, G2; 17.5 and 35 cm; 30, 50, and 80 seeds m-2); dry bean (Phaseolus vulgaris L.) (35 and 52.5 cm; 0, 60 N) and barley (Hordeum vulgare L.) in Year 1 followed by wheat (Triticum aestivum L.) in Year 2. Another experiment was soybean, dry bean and barley (Year 1); wheat (0, 30, 60, 90, 120, 150 N) - Year 2. The economic optimum plant density (EOPD) for soybean under irrigation was 47 plants m-2. N saving recommendation for following wheat was 30 kg ha-1 (soybean), 26 kg ha-1 (dry bean). The study confirmed strong relationships between environment and soil N benefits by these legumes for subsequent wheat in southern Alberta.