Biomass productivity and bromatological composition of forage oat genotypes in Vitória da Conquista, BA

Abstract

The present study was conducted with the objective of evaluating and selecting forage oat genotypes adapted to the edaphoclimatic conditions of Vitória da Conquista, municipality located in a tropical region of altitude in the state of Bahia. It was used the experimental design in randomized blocks, with three replicates and nine treatments, constituted by the genotypes São Carlos, UPF 86081, FAPA 2, FAPA 43, UPF 15, IAPAR 61, UPF 19, IPR 126, UFRGS 16. The seeding was performed manually, after plowing and soil harrowing, in May 2006. The nitrogen fertilization varied from 80 to 120 kg ha^-1 of N, divided in applications at the time of planting, 20 days after planting and after each cut. In periods of low water availability was used additional irrigation via sprinkling. The first cut was performed at the beginning of rubber and the following cuts, when the plants reached height between 35 and 40 cm. Were evaluated the number of days from emergence to flowering and the number of days of emergence to maturing of the grains to determine the growth cycle of the genotypes. Throughout the essay, were evaluated the green mass production and dry mass and the bromatological composition, determining the levels of crude protein, neutral detergent fiber, acid detergent fiber and in vitro digestibility of the dry matter. The genotypes UPF 86081, UPF 19 and UFRGS 16 presented potential of use in the region, in the winter period, with higher productivity of green biomass, while the genotypes FAPA 43, FAPA 2, IPR 126, IAPAR 61, UPF 15 and São Carlos show better bromatological performance with reduced fiber content and higher dry matter digestibility.