Efeitos das deficiências de alguns micronutrientes em dois cultivares (Santa Rosa e UFV-1) de soja (Glycine max (L.) Merill)

Two soybean varieties were grown in nutrient solution either in the presence on in the absence of B, Cu and Zn. Symptoms of deficiency were observed. Dry matter production and yield data were recorded. Leaf analyses were made in the end of the pod filling period (except in the case of the minus B treatment in which plants failed to produce grains). Main conclusions were the following: (1) lack of B in the substrate affected dry matter production more than the deficiencies of Cu and Zn; (2) Cu deficiency reduced growth and yield formation more than the lack of Zn; (3) symtoms of deficiency are in agreement with those already described; (4) variety UFV-1 seems more sensitive to the deficiency of micronutrients than Santa Rosa; (5) leaf levels of B and Zn indicative of adequate nutritional status seem to be different for the two varieties.Os cultivares de soja Santa Rosa e UFV-1 foram cultivados em solução nutritiva deficiente em B, Cu ou Zn. As plantas carentes em B não completaram o ciclo, enquanto as demais o fizeram. A carência de Cu afetou a produção de matéria seca e a de vagens mais que a falta de Zn. Quantitativamente, as deficiências induzidas afetaram a variedade UFV - 1 mais que a Santa Rosa