Assessing the Effectiveness of Zn Acetate and Oxide as Alternatives for Corn and Soybean Seed Treatment in Sandy and Clay Soil

Zinc (Zn) is the micronutrient with the lowest availability in agricultural soils, and consequently 50 % of the world’s soils present Zn deficient. To test the viability of alternative Zn sources (Zn acetate and Zn oxide) to corn and soybean seed treatments, we ran an experiment using these two alternatives at contrasting application rates (0; 0.25; 0.50; 0.76 and 1.01 g kg-1) applied to soybean and corn seeds that were subsequently sowed in sandy and clay soils. We measured- Zn accumulation, dry matter and germination, and analyzed this data using uni (LSD-test) and multivariate analysis (Principal Component Analysis, PCA). Results of the PCA showed that the sandy soil yielded higher dry matter and Zn accumulation than the clay soil. The corn provided higher dry matter while the soybean showed enhanced Zn accumulation and germination. The LSD test showed that corn presented positive Zn accumulation in response to Zn rates in both sandy and clay soil. For soybeans, this effect was only observed in sandy soil, while the clay soil presented decreases in dry matter and germination due to Zn rates. Overall, our findings reveal that both Zn acetate and Zn oxide are viable alternatives for supplying Zn to corn seed treatment in sandy and clay soil, and to soybean seed treatment in sandy soil. We suggest that more research should be undertaken to understand the response of soybean seed treatments to Zn supply, especially in clay soil.