CORRETIVO NANOPARTICULADO APLICADO NO MILHO SOLTEIRO E CONSORCIADO COM Urochloa brizantha cv. Piatã

Abstract

The efficiency of soil correction and the availability of Ca 2+ and Mg 2+ for maize (Zeamays) can be improved through the use of limestone nanoparticles due to nano- technology (particles in nm). The objective of this research was to analyze a corrective soil acidity material based on nanoparticulate calcium carbonate, its effects on soil chemical attributes, and agronomic performance in single maize cultivation, in intercropping with Urochloa brizantha cv. Piatã, and in pasture cultivated in succession. Two trials were conducted: a) maize cultivation in the main crop; b) maize intercropped with U. brizantha cv. Piatã in the main crop, c) pasture in the off-season. Treatments consisted of nanoparticulate limestone (NL) and/or conventional limestone (CL) application in the following proportions, according to liming requirement (LR): T1- 100%CL; T2- 100% NL; T3- 50% CL + 50% NL; T4- 75% CL + 25% NL; T5- 25% CL + 75% NL; and T6 – control without LR correction. The six treatments, in both trials, were arranged in randomized blocks with four replications. pH CaCl2, P, Ca, Mg, K, H+Al, Al, aluminum saturation, sum, and base saturation were evaluated at depths of 0-20 and 20-40 cm after maize and pasture exploitation. For maize, plant height, ear insertion, stemdiameter were evaluated, and at harvest, yield components were assessed. For U. Brizantha cv. Piatã pasture, pasture formation, leaf/stem ratio, forage yield, and regrowth yield were evaluated. Results were subjected to analysis of variance and when significant, contrasted with Duncan's test at 10%. Exclusive or combined applications of corrective measures were not sufficient to increase crop yields. However, they alter soil attributes contributing to acidity reduction. It is worth noting that the effect of correctives is evidentin the more superficial layers and over a longer period (12 months), the effect is visualizedin the subsoil.