Characteristics and classification of the quality and productive standards of the mombaça grass under a livestock-forest system or full sun

Abstract

The objective of this study is to identify qualitative and productive changes in Mombasa grass under a livestock-forest system or full sun and to classify the variables that are most relevant for evaluating the qualitative performance of these systems. The experiments were conducted in shade areas, with four replications for each of the 12 treatments, including four growth cycles and three levels of shading in Mombasa grass, totaling 48 experimental units. Calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), nitrogen (N) and dry mass production (DMP) (kg ha-1) were used as discriminatory variables for the shading groups. The levels of nutrients and shading in Mombaça grass were classified using Fisher multivariate discriminant analysis (FMDA). The FDMA indicated that Mg, K, P, N, and DMP formed a discriminant function. However, DMP was the least important variable for identifying the groups. Five groups were pre-defined before FDMA: MFS 2 (Mombasa grass in full sun in the second cycle), MFS 6 (Mombasa grass in full sun in the sixth cycle), MFS 7 (Mombasa grass in full sun in the seventh cycle), M25 4 (Mombasa grass at 25% shading in the fourth cycle), and M25 7 (Mombasa grass at 25% shading in the seventh cycle). The results indicate that Mg, P, K, and N are helpful for identifying new genotypes of plants grown on shading conditions because of the responsiveness and stability of these elements to environmental changes.