Basalt rock powder and organic compounds in corn crops

The use of basalt rock powder associated with an organic fertilizer with compost can be an option to reduce the use of soluble fertilizers. Thus, this study aimed to evaluate the effect of organic compost and basalt rock powder on the agronomic traits of the corn crop and on the levels of nutrients available in the soil solution, with two additional treatments of fertilization with NPK. The experimental design used was completely randomized blocks, in a factorial scheme (5x2) + 2, with two additional and four replications. The first factor consisted of five doses of organic compost (0, 4, 6, 8 and 10 t ha-1) and the second factor, with and without basalt rock dust (0 and 8 t ha-1). The additional treatment consisted of the application of 150 kg ha-1 of formulated NPK (10-15-15), equivalent to ½ of the recommended dose for the crop, associated with 8 t ha-1 of basalt rock powder and the second additional treatment consisted in the application of 300 kg ha-1 of formulated 10-15-15 of NPK and without rock dust. The agronomic characteristics of corn and the nutrient contents in the soil solution were evaluated. The results showed that the use of organic compost associated with rock dust promoted soil chemical improvements, especially pH elevation and calcium content increase. There was no effect of organic compost with rock powder on the agronomic characteristics of corn evaluated. The use of chemical fertilizer of an NPK formulation improved the corn crop compared to the use of organic compost and rock dust. The application of 8 t ha-1 of basalt rock powder, associated with 150 kg ha-1 of a formulated NPK improved the development of the corn crop compared to the use of 300 kg ha-1.