Fertilizer Management Strategies of Glycine max L. (Soybean) in Northcentral and North-Western North Dakota

Abstract

Soybean (Glycine max L.) is a new cash crop grown in north central and northwestern North Dakota (ND). Soils and climate in these new soybean areas differ from current fertilizer guidelines. A three-year study to evaluate soybean fertility best management practices was initiated in the spring of 2016 and concluded in 2018. Each year had two sites and twelve treatments. One site was acidic (pH < 6.2) and the other was alkaline (pH > 7.2). Both site treatments were: untreated check, inoculated with rhizobia (Bradyrhizobium japonicum L.), broadcast urea (55 kg ha−1), broadcast MAP (110 kg ha−1), In-furrow 10-34-0 (28 L ha−1), in-furrow 6-24-6 (28 L ha−1), foliar 3-18-18 (28 L ha−1) at V5 and R2, and foliar 3-18-18 (28 L ha−1) with sulfate (1.1 kg ha−1) at V5 and R2. The acidic site had two treatments of sugar beet (Beta vulgaris L.) waste lime (4411 kg ha−1 and 8821 kg ha−1). The alkaline site received treatments of iron ortho-ortho-EDDHA (7.1 L ha−1), and naked ortho-ortho-EDDHA (7.1 L ha−1). An in-furrow treatment of cobalt (2.9 kg cobalt-sulfate ha−1) was added in 2018. Fertilizer treatments did not impact soybean yield, protein content and oil content at the 0.05 significance level.