Characterization of nutritional deficiences on low lands of the cerrado region

Abstract

The effect of lime, S, Cu, Zn, B and Mo on the dry matter yield, number and dry weight of nodules of soybean (Glycine max (L) Merrill), variety Doko, was evaluated in ten paddy soils of the Cerrado Region. The soils showed a largo difference in their chemical and physical properties. The experimental design was an incomplete 2⁶ factorial with two replications. The nutrients were applied on the basis of mg of each element per liter of dry soil (mg/1 ): 0 and 30 of S (elemental sulphur), 0 and 2 of Cu (CuCl), 0 and 3 of Zn (ZnO), 0 and 0.5 of B (H₃BO₃), 0 and 0.25 of Mo (Na₂MoO₄2H₂O), and, 0 and a quantity of lime determined by the SMP method sufficient to increase the pH of each soil to 5.5. A basic fertilization was used (mg/l): 100 of P and 127 of K (KH₂PO₄) and 73 of K (KCl). Eight out of the ten soils responded to lime. For the parameters evaluated (dry matter yield, number and dry weight of nodules), the response of the nutrients was in the following sequence: B>S>Cu>Zn. There was no effect of Mo on any of these parameters. An effect of the interactions lime x B, lime x S, lime x Zn, Cu x Zn and S x B on the dry matter yield, number and dry weight of nodules was observed.