Response of different Urochloa pastures to liming, cultivated in Sabana de Manacas region, Cuba

Resumen

The response of four pasture species to liming, cultivated in a ferruginous nodular gley soil (plintosol) from Sabana de Manacas region, Cuba, was evaluated. Four doses of lime (0, 2, 4 and 6 t ha-1 of CaCO3) were studied in Urochloa brizantha cv. Marandú, Urochloa decumbens cv. CIAT-602, Urochloa hybrid cv. Mulato II and Urochloa hybrid cv. Yacaré, in a random block design with factorial arrangement and four replications. The experiment lasted three years and the variables that characterized soil acidity were evaluated, as well as the concentrations of biomass macronutrients and yields. Liming significantly increased (P <0.01) exchangeable Ca content (6.1 cmolc kg-1), pH in H2O (6.9), cation exchange capacity (7.3 cmolc kg-1) and the percentage of base saturation
(94 %), and the exchangeable acidity of soil decreased (0.91 cmolc kg-1). The best effects were achieved with the dose of 6 t ha-1. With 4 and 6 t ha-1, the highest Ca concentrations (P < 0.01) in the biomass (5.5 g kg-1 of dry mass) and the highest yields (up to 11.7 t ha-1) were obtained. The effectiveness of liming was maintained for two years. It is concluded that liming improves calcium nutrition and increases productivity of pastures
of Brachiaria genus, cultivated in an acid soil with low fertility, in Sabana de Manacas region. Its greatest effects on soil and yields are maintained during the first two years. The application of 4 ha-1 of lime is recommended.
Keywords: soil acidity, liming, forage species, forage yield