Effects of Three Pulse Crops on Subsequent Barley, Canola, and Wheat

Diverse crop rotations are an important part of sustainable agricultural systems. Crop sequence can affect rotational benefits. Our objectives were to assess the N dynamics of barley (Hordeum vulgare L.), canola (Brassica napus L.), faba bean (Vicia faba L.), lupin (Lupinus angustifolius L.), and pea (Pisum sativum L.) crops in the first year (YR1) of a rotation, and quantify the rotational effects of these crops on subsequent yield and protein content of barley, canola, and wheat (Triticum aestivum L.) crops in the second year (YR2) of the rotation. Twenty-one crop sequences were assessed. In YR1 tannin-free faba bean, narrow-leafed lupin, and field pea were grown without N fertilizer and barley and canola were grown with and without N fertilizer. These seven treatments were followed by three subsequent crops; barley, canola, and wheat. Faba bean had the highest potential for N fixation followed by pea and lupin. Nitrogen returned to the soil in aboveground crop residues was similar across pulse species. Faba bean and pea stubble were able to maintain the yield and quality of subsequent barley, canola, and wheat crops without the addition of N fertilizer. Pulse crops can improve the sustainability of the Alberta cropping system.