TILLER DEFOLIATION ON SIGNAL GRASS PASTURES UNDER CONTINUOUS STOCKING

• Autor(a) principal: Santos, Manoel Eduardo R.
• Data de Publicação: 2011
• Outros Autores: da Fonseca, Dilermando Miranda, Gomes, Virgilio Mesquita, Sant’Anna e Castro, Marina R., de Carvalho, Victor Valério
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Ciência animal brasileira (Online)
• Texto Completo: https://revistas.ufg.br/vet/article/view/7541
• topic: Forragiculture; Brachiaria decumbens; composição morfológica; número de perfilho; pastejo; variabilidade espacial da vegetação

The objective of this study was to evaluate the number of tillers with different levels of defoliation and their characteristics on the Brachiaria decumbens cv. Basilisk pasture. Three different areas on the pasture (undergrazed, with proper grazing and overgrazed) and three tiller categories (without defoliation, with defoliation and without shoot apical meristem) were evaluated. Randomized block design with three repetitions was used. The B. decumbens pasture was managed under the continuous stocking system with cattle, and the grass height was kept at about 25cm. The number of tillers showing defoliation was higher (1,333 tillers/m²) for the overgrazed area compared to the area with proper grazing and the undergrazed area. Inverse response pattern was observed for the tillers without defoliation. On the other hand, the number of tillers without the shoot apical meristem was higher in the areas with proper grazing (395 tillers/m²). Tillers without defoliation showed a lower pseudoculm length (10.3cm) and a smaller number of dead leaves (0.22) when compared to the other categories. The length of the leaf blade did not change for the tiller categories evaluated. The number of grazed leaves was lower for tillers without the shoot apical meristem in relation to the ones showing or not defoliation. Lower leaf area for the tillers that had the shoot apical meristem removed was observed. Tillers without the shoot apical meristem showed a lower percentage of green leaf blade (GLB), higher percentages of both live culm (LC) and dead leaf blade (DLB) as well as a lower relation of the GLB/LC and weight comparing to the tillers showing or not defoliation. Those last ones did not differ regarding their morphological composition. There is indeed spatial variability of the vegetation and tiller diversity with varying levels of defoliation on Brachiaria decumbens cv. Basilisk pastures under continuous grazing.KEYWORDS: Brachiaria decumbens; grazing;  morphological composition; number of tillers; spatial variability of the vegetation.