R. Bras. Zootec.01/Aug/2006;35(4):1298-307.
Morphogenetic and structural traits of italian ryegrass (Lolium multiflorum Lam.) sward managed under different grazing intensities and methods
DOI: 10.1590/S1516-35982006000500007
The trial was conducted to determine the influences of grazing intensity and grazing method on morphogenetic (leaf elongation rate, leaf appearance rate, leaf lifespan) and structural (number of green leaves, length of leaves and tiller density) traits in italian ryegrass sward. The experimental treatments stemmed from a 2 x 2 factorial combination of two grazing intensities and two grazing methods (continuous and rotational). The experimental design was completely randomized block with four replications. Thirty tillers were marked per experimental unit. The grazing intensity brought about differences in the morphogenic and structural traits of the sward. Low grazing intensity resulted in higher leaf elongation rate and in lower tiller density, higher length of leaves and higher number of live leaves per tiller. The grazing methods influenced the morphogenetic and structural traits. Continuous grazing resulted in higher leaf elongation rate, higher leaf appearance rate, longer leaf lifespan in the first grazing cycle, and in higher tiller density. There was a grazing intensity by grazing cycle interaction. It is concluded that grazing intensity and grazing method exert marked effect on the morphogenetic and structural traits of the grazed sward.