Location: Crop Production Systems ResearchTitle: Soybean micronutrient content in irrigated plants grown in the Midsouth Author
Submitted to: Communications in Soil Science and Plant Analysis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2016
Publication Date: 3/20/2017
Citation: Bruns, H.A. 2017. Soybean micronutrient content in irrigated plants grown in the Midsouth. Communications in Soil Science and Plant Analysis. doi:10.1080/00103624.2017.1299165.
Interpretive Summary: Information on the uptake of micronutrients by irrigated soybean grown in the Early Soybean Production System common to the Midsouth is unavailable and may be useful in improving fertilizer recommendations for the crop. A USDA-ARS scientist has completed an experiment that determined the amount of iron, boron, zinc, manganese, and copper in the leaves, stems, pods, and seed throughout the season of three popular soybean varieties. Two sites were used, a sandy loam soil and a heavy clay. No differences in micronutrient concentrations or total contents in the various plant parts occurred between the two sites, years, or the three varieties. No deficiencies symptoms nor micronutrient toxicities were observed. This research found that a 48 bu/A seed yield will remove only about 4.6 oz/A of iron, 2.2 oz/A of boron, 2.5 oz/A of zinc, 1.4 oz/A of manganese, and 0.7 oz/A of copper.
Technical Abstract: Micronutrients are essential to soybean (Glycine max L. Merr.) but required in minute quantities. Concentrations and tissue contents of Fe, B, Zn, Mn and Cu were determined for two MG IV and one MG V irrigated cultivars grown in twin-rows in the Mississippi Delta on clay and sandy loam soil sites in 2011 and 2012. Plants were sampled at growth stages V3, R2, R4, R6 and R8, their tissues separated, dried, weighed and ground for determining nutrient concentrations. Total nutrient contents were calculated from these data. No cultivar, site or year differences in concentrations or contents of the nutrients were observed. Iron had the greatest concentration and total tissue content of all elements at all growth stages, followed by B, Zn, Mn and Cu. Due to the elements being immobile, maximum concentrations and contents in leaves was acquired at R4 and then declined as leaves senesced. In stems both concentrations and contents remained constant or increased during this time while seed containing pods rapidly increased until (R8). These data show a 3328 kg ha-1 seed yield will remove about 325.0 g Fe ha-1, 153.9 g B ha-1, 175.6 g Zn ha-1, 100.0 g Mn ha-1 and 52.5 g Cu ha-1.