Desempenho de híbridos de urochloa para a produção de forragem na Amazônia Legal

Abstract

The objective of this work was to evaluate under the edaphoclimatic conditions of the Amazon and Cerrado ecotone the performance of Urochloa hybrids in relation to Marandu grass (Urochloa brizantha cv. Marandu). The agronomic characteristics of 30 forage hybrids plus Marandu grass (control) were evaluated, according to a completely randomized design, with 31 treatments, three replications, totaling 93 experimental units. The variables analyzed were: Height, anual forage production, percentage of morphological components, leaf blade, steam and dead material, rate of forage accumulation, presence of diseases and pest attacks. For all the variables evaluated, there was at least one grass that varied from the control. In general, it was found that Marandu grass was classified in the group of foragers with the highest production, however, only three hybrids showed less production. Regarding the height of the forage canopy, only seven of the thirty hybrids showed the same height pattern as Marandu grass. However, in relation to the anual forage production, no hybrid surpassed Marandu grass, however, only two hybrids showed inferior production. In general, the hybrids showed a higher proportion of leaf blade, and a smller proportion of stems and dead material than Marandu grass. Regarding pests and diseases, the presence of diseases was not verified, and the level of damage to sharpshooters was probably absent, due to the área being new. Finally, although no hybrid has exceeded the annual productions of Marandu grass, the differendiated partition for most hybrids, for the benefit of the formation of leaf blades, as well as the size of the plant, may probably have som hybrid with the potential to improve grazing animal production in relation to Marandu grass.