Boletim de Indústria Animal (Jan 2011)
Tiller diversity on Brachiaria decumbens pasture managed under continuos stocking
Abstract
The experiment was carried out aiming to classify and quantify tiller categories of Brachiaria decumbens cv. Basilisk from different heights found on the same pasture. Four different plant heights (10; 20; 30 and 40 cm) living at the same pasture were evaluated. Randomized block design with three replications was used. Tillers were classified according to their stage of development, growth origin, defoliation level and size. The number of vegetative tillers reduced linearly, while the number of reproductive tillers and dead tillers increased linearly according to the plant height. The number of aerial tillers showed a quadratic response in relation to the plant height. The pastures having grasses of 10, 20, 30 and 40 cm in height had respectively 292, 408, 496 and 344 aerial tillers/m2. The population density of defoliated tillers reduced linearly according to the plant height. The population density of tillers without the apical shoot showed quadratic response to the signal grass height, being the smallest values found for places having grasses of 10 cm (176 tillers/m2) and 40 cm (180 tillers/m2) in height. The number of tillers without defoliation quadratic responded to the plant height, being the highest values found for places having grasses extremely high. The areas with the highest grasses also showed the highest numbers of tallest tillers. There is indeed a spatial variability of the vegetation and a high morphological diversity of tillers on Brachiaria decumbens cv. Basilisk pastures managed under the continuous stocking system.