The micronutrients copper and zinc have important functions in vegeatable metabolism, but studies about micronutrient needs for sorghum are scarce. Aiming to evaluate the effect of copper and zinc application in nutritional attributes of sorghum an experiment was carried out in a randomized block experimental design with a combination of five doses of copper (0, 0.26, 0.90, 1.54 and 1.80 mg kg-1) and five doses of zinc (0, 0.32, 1.1, 1.88 and 2.2 mg kg-1) combined by Box Central Composite design, resulting in nine treatments, which were applied in three soil classes (Latosol, Alfisol and Entisol), with three replications. Ninety six days after sowing, nutrients contents and accumulation and protein contents were determined. The copper application increased nitrogen, phosphorus, potassium and copper contents and crude protein content in grains, however, the same results were not observed for zinc application. Alfisol was the soil most responsive to the application of nutrients.
Sorghum bicolor; micronutrients; mineral nutrition
