Nutrient Uptake of Corn, Soybean, and Hard Red Spring Wheat Following the Application of Chelate Sources on the Seed.

Chelation prevents oxidation and precipitation of micronutrients in the soil solution and makes available for plant uptake. The functionality of a chelate on micronutrients depends primarily on soil pH. Our objective was to determine if the use of chelates would enhance early growth and micronutrient uptake for corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and hard red spring wheat (Triticum aestivum L.). Two separate greenhouse studies were conducted in which five chelate sources (citric acid, DTPA, EDDHA, EDTA, and oxalic acid) were evaluated in Study 1 and four chelate rates (0, 0.08, 0.16, and 0.24 mol ha^-1) of DTPA, EDDHA, and EDTA were evaluated in Study 2 on acidic, near neutral, and alkaline soils. All treatments were applied in liquid on the seed. In Study 1, early corn growth was not affected by soil type and chelate source. Early soybean growth was affected by soil type. Use of citric acid enhanced early growth of wheat and was affected by soil type. Except P and S, all other nutrients were affected by soil type but none of them were affected by chelate source in corn. Boron and Cu uptake were not affected in soybean but other nutrients were affected by soil type. Only Mn uptake in soybean was affected by chelate source.  Soil type affected all nutrient uptake in wheat. In Study 2, early growth of all three crops were not affected by chelate rate. Corn P, Mn, Cu, and Zn uptake was affected by chelate rate and Fe, Mn, and Zn uptake was affected in soybean. Micronutrient uptake in wheat was not affected by chelate rate. These results suggest that the use of chelate can enhance uptake of some micronutrients.