Forrageiras de clima tropical em solos de várzea da fronteira oeste do Rio Grande do Sul

Abstract

Tropical grasses are alternatives for feeding ruminants in western RS region, even in lowland soils that have poor drainage because of its low water infiltration. This experiment aimed to determine the productivity and nutritional quality of Millet (Pennisetum americanum (L.), Sorghum (Sorghum bicolor), Brachiaria (Brachiaria -. cv Xaraés) and Sudan Grass (Sorghum sudanense) in lowland soils in the western Rio Grande do Sul. It was conducted two experiments in the city of Itaqui (RS). The experiment 1 was carried out from 28/12/13 to 21/04/14. It was evaluated two varieties of millet (BRS 1501 and Hybrid) and Sudan grass (IPA Sudam 4202) in a randomized block design with four blocks. It was determined dry matter production (kg DM/ha) and the chemical composition of materials. In the experiment 2 it was evaluated four species of tropical grasses: Sorghum 2501C, Millet BRS 1503, Sudan grass BRS Estribo and Braquiária MG5 Xaraés, who received the same cultivation, handling cuts and manage tracts descript in the experiment 1. In experiment 1 the materials were similar to each other, and the forage production reduced as the cuts were made. In the total dry matter production there was no statistical difference between averaging 8630 DM kg/ha. Comparing the cuts made in the pasture, the dry matter production was higher in the first and second one. In the chemical composition analysis, the crude protein from Millet hybrid levels were higher than Sudan grass being millet, with 23.61%, hybrid 24.75% and Sudan grass with 20.75%. NDF and ADL, had no significant difference between them.