Produção e composição bromatológica de genótipos de capim-buffel no semiárido mineiro

Abstract

Buffel grass (Cenchrus ciliaris L.) is one of the main forage grasses used in conventional pastures in hot semi-arid environments. However, the limited number of registered cultivars in Brazil restricts access to cultivation information and, consequently, hinders the dissemination of this forage species in the country. Therefore, the objective of this study was to select buffel grass genotypes (Áridus, Buffel 131, Biloela, Comum, Grass, and USA) based on productive, morphological, and nutritional traits for cultivation in the semi-arid region of Minas Gerais, Brazil. The experimental design consisted of a randomized complete block design with six replicates in a split-plot scheme (6 × 2), where genotypes were allocated to the main plots and years to the subplots. The variables evaluated were plant height, total forage yield, leaf yield, leaf:stem ratio, and the chemical and morphological composition of the biomass. Genotypic variation independently influenced the agronomic and morphological traits, while the year of evaluation affected all traits. In the first year, forage production was higher, whereas morphological and bromatological composition was superior in the second year. A significant interaction between genotype and year was observed only for inflorescence percentage and for neutral and acid detergent fiber (NDF and ADF) contents during the rainy season, and for ash (mineral matter, MM) content during the dry season. The genotypes Biloela and Áridus stood out for their greater plant height and higher forage and leaf yields, while Grass exhibited the highest leaf:stem ratio. Buffel 131 showed the lowest fiber content and the smallest increases in NDF and ADF levels over the evaluation years, compared to the other genotypes. In conclusion, Biloela and Áridus demonstrated higher productivity and better adaptation to local conditions. Buffel 131 showed superior morphological and bromatological composition, indicating potential for producing higher-quality forage. The significant effect of the year on the evaluated traits reinforces the importance of accounting for this factor in studies involving buffel grass genotypes in the semi-arid region of Minas Gerais.