Competition between species in mixture of Calopogonium mucunoides; Centrosema acutifolium and Brachiaria decumbens STAPF

Abstract

A field experiment was conducted in plots, with the objective of determing the competitiveness between Brachiaria decumbens (DEC), Calopogonium mucunoides (CAL) and Centrosema acutipolium (CEN) planted in consorciation. Plots of 2,3 x 3,0 m were established in a Red Alic Latosol, either with and without N, P, Ca, Mg, Mo, B and Zn fertilization, with 3 replications. As a treatment, a line of 1.0 m was planted at the middle of the plot, with 10 plants of cach species, to establish monoculture and consorciation between the group. The 10 plants of the central line were harvested 150 days after being planted, for the dry matter (MS) determination and the analysis of the N, P, K, Ca and Mg contents in the MS. For each determination, the potential of competition between species was measured through the Coefficient of Aggression «A». The results have shown that CAL was the most competitive species in relation to the others, for all parameters analysed. CEN was the least competitive one, while DEC was intermediate between both leguminosae. Among the nutrients measured, the competition for K between DEC and CEN appears to be the principal limitation in the mixture.