Biochar de resíduos de açaí como condicionador do solo na produção e nutrição de plantas forrageiras

Abstract

Achieving viable and less polluting production leads to continuous searches for nutrient sources that are efficient, economical and more accessible to producers. Biochar is a mineral material rich in carbon and nutrients, acting as a soil conditioner to improve chemical, physical and biological conditions, improving absorption and reducing nutrient loss in agricultural soils. In this study, the objective was to evaluate the growth, production and nutrition of the forages Panicum maximum (Cv. Mombaça) and Pennisetum purpureum Schum (Cv. BRS Kurumi), grown in cerrado soil subjected to the application of açaí seed biochar. The work was carried out in a greenhouse, at the Instituto Federal do Amapá - Campus Agrícola Porto Grande. The experimental design used was completely randomized (DIC), arranged in a 5x2 factorial scheme, with four replications, totaling 40 experimental units. The factors consisted of the control treatment (without biochar application) and four concentrations of açaí seed biochar (0; 0.125; 0.25; 0.375 and 0.5%) and two forage species, P. maximum cv. Mombasa and P. purpureum Schum cv. BRS Kurumi. The soil of the experiment was characterized as a Dystrophic Yellow Oxisol with a sandy loam texture, in a cerrado area in the municipality of Porto Grande/AP. Liming was carried out 30 days before applying the treatments and concentrations of açaí seed biochar were applied 15 days before sowing, for reaction and stabilization. After 90 days of cultivation, the plant's height, diameter, number of tillers and leaves, leaf, stem and root dry matter were determined, followed by nutrient content in the plant tissue. The concentrations of biochar applied to the soil showed a difference (p<0.05 and p<0.01) for the number of tillers, leaf and stem dry matter. The species P. maximum was superior for most variables, with the exception of stem diameter and root dry mass. The macronutrients present in the leaves were different (p<0.01) for P, K and Mg, while in the stem it was different (p<0.01) for P, K and Ca. The chemical attributes of the soil were higher at concentration 0.375 P. maximum and 0.5 for P. purpureum Schum. Biochar concentrations provide nutrients for forage plants in the soil, and the species P. maximum (Cv. Mombaça) has greater development compared to P. purpureum Schum (Cv. BRS Kurumi).