Componentes produtivos, morfológicos e químicos do capim marandu cultivado com fontes e doses de silicato

Abstract

The research was developed at the Campus Experimental Farm of Janaúba, State University of Montes Claros - UNIMONTES. The objective of this study was to evaluate the response of the productive, morphological and chemical characteristics of the marandu grass (Urochloa brizantha (Hoschst Ex A. Rich) RD Webster cv Marandu [syn. Brachiaria brizantha (Hochst. Ex A. Rich.) Stapf cv Marandu] influenced by sources and doses of calcium and magnesium silicate. The experimental design was the randomized blocks with factorial scheme (6 x 2) + 1, corresponding to six silicon doses (400, 800, 1200, 1600, 2000, 2400 kg ha-1 ), two silicon sources (Agrosilicon ®and Yoorin ®), a control (Limestone) with four replicates. The work was conducted in the summer season between December 2016 and April 2017, with three evaluation cuts being performed, the average of these cuts being considered as final results. The production of green and dry matter was evaluated considering the productive characteristics, the proportion of leaf blade, stalk and dead matter and blade/stem ratio, considering morphological characteristics and the levels of neutral detergent fiber, acid detergent fiber, lignin, and crude protein as chemical characteristics. The characteristics studied, except crude protein, did not present difference for the sources compared to the control, as well as they did not have interaction between sources and doses. For the crude protein interaction between sources and doses of silicate occurred. Among the doses, it was observed that the means were adjusted to the linear and quadratic regression model for Agrosilicon® and Yoorin®, respectively. The use of calcium and magnesium silicate sources did not present differences compared to limestone for the characteristics under study. The crude protein contents presented differences for the silicate sources, and Agrosilicon® stands out for Yoorin® when used at the dose of 400 kg ha-1.