Morfogênese de pastagens de milheto e capim sudão submetidas ao pastejo contínuo

Abstract

The aim of this study was to compare morphogenetic parameters of sudangrass and millet pastures in the Central Depression of Rio Grande do Sul, managed by continuous grazing. The pastures were subdivided into two periods of evaluation. The treatments consisted of pearl millet (Pennisetum americanum (L.) Leeke) and sudangrass (Sorghum bicolor cv. Sudanense), both submitted to continuous grazing by culling cows. The experimental design was completely randomized with two treatments and two periods. The canopy height (32.69 vs 20.29 cm), leaf appearance rate (0.147 vs 0.080) , total number of leaves per tiller (4.74 vs 3,06), number of green leaves (4.26 vs 2.55), number of young leaves (1.92 vs 1.47) and number of mature leaves (2.34 vs 1.08) were higher in millet tillers, while the rate of senescence was higher in sudangrass tillers (0.511 cm) compared to millet tillers (0.495 cm). The total number of leaves (4.28 vs 3.53) and the number of dead leaves (0.58 vs 0.38) were higher during the initial grazing cycle. Millet pastures have a greater vegetative growth potential during grazing than sudangrass pastures.