Uso do pó de basalto como remineralizador do solo em pastagem de Urochloa brizantha cv marandú e seus efeitos na qualidade do solo e produtividade da cultura

Abstract

Despite being a large producer of cattle, Brazil has many pasture areas in an advanced stage of degradation. Basalt powder appears as an alternative remineralizer, as it is abundant in the Uberlândia region, as an input with low added value, to make up for correction needs, and supplementation with fertilizers. This study aimed to evaluate the use of different doses of basalt powder in the development and nutritional quality of pastures formed by Urochloa brizantha cv Marandú. The design used was completely randomized, in plots subdivided over time, where nine doses of basalt dust applied in planting 1 – Zero dose (without basalt dust) were evaluated; 2 – 2.0; 3 – 4.0; 4 – 6.0; 5 – 8.0, 6 – 10.0; 7 -12.0; 8 – 14.0 e; 9 – 16 t ha-1 of basalt dust and; 10 – Mineral fertilization, with the application of 300 kg ha-1 of mineral formula 08-28-16, with 3 repetitions. Productivity assessments (MF and MS) were carried out at 60, 12 and 180 days after application of treatments (DAAT), foliar analysis of plant tissues (180 and 365 DAAT), and soil chemical attributes (270 DAAT). The production of fresh mass (FM) and dry mass (DM) of brachiaria was significantly higher at a dose of 6 t ha-1, in relation to conventional mineral fertilization. At 180 days after a dose of 8 t ha-1 of basalt powder, the most significant nutritional accumulations were observed in the plants for most of the nutrients evaluated. No significant impacts were observed on soil pH and CEC, nor on macronutrients (P, K, Ca, S, Mg), however, higher levels of micronutrients were observed in the soil (B, Cu, Fe, Mn and Zn), which they surpass or are equivalent to conventional mineral fertilizers, however, in higher doses (14 t ha -1) which can make their use more expensive and unfeasible. More time for evaluation and new studies are suggested to prove the viability, interaction and residual of basalt dust in the soil.