Yield and water use efficiency of winter peas planted in cereal residues

Abstract

Sowing pulse crops into the residue of former cereal crops, such as winter wheat (Triticum aestivum), has been shown to provide numerous crop benefits. Straw left behind creates a favorable microhabitat for plant overwintering and water conservation by moderating soil temperature, diminishing the influence of solar radiation, and cutting potential evaporation during the summer growing season. This research project examined three hypotheses involving winter peas (Pisum sativum L.): i. Do winter peas planted no-till in standing cereal residue yield more kg ha-1 of edible grain than winter peas planted in disc harrowed cereal residue, ii. Do winter peas have higher water use efficiency (WUE) kg ha-1 mm-1 when planted in standing wheat and triticale residue versus winter peas planted in conventionally tilled cereal residue, and iii. Is it economically profitable to incorporate winter peas as part of a cereal-winter pea rotation in place of a continuous winter wheat rotation. Winter peas planted into standing cereal residue improved grain yield but did not significantly improve water use efficiency as compared to planting into soil prepared with a tandem disc harrow. Economic enterprise and partial budgets determined that a change to winter wheat-winter pea rotation versus continuous winter wheat produced a net economic loss.