Características morfológicas do capim-elefante e capim-braquiarão submetidos a diferentes taxas de lotação

Abstract

This work evaluated some forage plant characteristics that could be utilized to determine the vegetal tissue turnover that allied tillers dynamics support in practice pasture management, aiming highest forage and animal yields. The experiment was carried out in South Extreme Experimental Station of Animal Science (CEPLAC), situated in Itabela - BA. The annual rainfall at that place is 1311mm and the mean temperature is 25ºC, without definite drought season. The soil is an Ultisol with the following values: pH in H2O = 6.2; Al = 0.1 cmolc/dm3; Ca = 2.6 cmolc/dm3; Mg = 0.4 cmolc/dm3; K = 0.2 cmolc/dm3 and P available = 2.9 mg/dm3. The experimental area consisted of 52 paddocks of P. purpureum and 52 of B. brizantha with 720 m2 each. The liming of the soil and fertilization of establishement were made at 1000 kg/ha of dolomitic limestone and 80 kg/ha of P2O5 and the maintenance fertilization at 160 kg/ha of N, 60 kg/ha of P2O5 and 120 kg/ha of K2O. Each grass was submitted to four stocking rates, in a rotational grazing system with three days of occupation and 36 days of rest, which resulted in a grazing cycle of 39 days. The stocking rates were 3, 4, 5 and 6 steers/ha, with mean body weigth of 280 kg. The stocking rates, in P. purpureum, affected significantly the tillers total height, stem height, apical meristem height, numbers of expanded completely and emergence leaves and the length of these two category of leaves. In B. brizantha the stocking rates affected the variables tillers total height, stem height, length of expanded completely and emergence leaves. With the increase of number of animals for unit of area (stocking rate) it was observed reduction in all the variables.