BIOCHAR: PRODUÇÃO E COMPOSIÇÃO NUTRICIONAL DE CULTIVARES DE CAPIM ELEFANTE

Abstract

This study aimed to evaluate the effect of different doses of Biochar on morphometric, productive, and bromatological characteristics of two elephant grass (Pennisetum purpureum Schum.) cultivars, BRS Capiaçu and BRS Kurumi, under irrigated conditions in the edaphoclimatic context of the Cerrado biome. The experiment was implemented at the Instituto Federal Goiano – Ceres Campus, using a randomized block design, with a factorial arrangement 2 (cultivars) x 4 (doses) and applied in plots subdivided in time (four periods), with four replications. The applied Biochar doses were 0, 8, 16, and 24 Mg ha⁻¹. Evaluations were performed at 71, 225, 335, and 447 days after application, assessing the following variables: dry matter yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude protein (CP). The results showed that the BRS Capiaçu cultivar presented a higher biomass accumulation, with superior DMY averages across all doses and evaluation periods. However, it also exhibited higher NDF and ADF contents, which may compromise forage digestibility. In contrast, BRS Kurumi stood out with higher CP levels and lower fiber concentrations, favoring its use in intensive dairy production systems. Analysis of variance indicated that Biochar doses did not significantly affect bromatological parameters, although they negatively influenced DMY at doses above 8 Mg ha⁻¹. Regression analyses revealed that the effects of Biochar varied over time, with a more pronounced impact observed during intermediate periods (200 to 300 days), possibly due to Biochar maturation in the soil and its interaction with the environment. It is concluded that although Biochar has potential as a soil conditioner, well-defined management strategies are required for its positive effects to be realized.