Desempenho nutricional de leguminosas consorciadas com milho (Zea mays) no oeste de Santa Catarina

Abstract

Green manuring is a practice that brings various benefits such as nutrient cycling, soil health conservation, and effective weed and disease control. With that said, the use of legumes in Brazilian crops is increasing, aiming to harness their biological nitrogen fixation capacity for the benefit of the intercropped or succeeding crop. This study aims to assess the amount of nitrogen potentially made available by legumes intercropped with corn, namely Estilosantes campo grande, Crotalaria spectabilis, and feijão guandu anão, in Campo Erê - SC. The experimental design was randomized blocks in a factorial split-plot arrangement, with four replications and 24 experimental units (EUs). The dimensions of the EUs were 6 meters in width by 4 meters in length, totaling 24 square meters. The blocks were subdivided into plots with and without nitrogen (N) topdressing, so that those with N topdressing received 150 kg ha−1 of N with corn at the V5 stage. For evaluations, plants from the cover crops were collected from 2 linear meters of each plot at two time points: first at the V5 stage of corn and second at the tasseling stage of corn. After collection, the cover crop plants were dried in an oven until reaching a constant weight. Once dried, they were ground and weighed to determine dry matter (DM) and subjected to sulfuric acid digestion to determine nutrient content. In conclusion, the cover crops significantly influenced all variables, proving essential for higher dry matter production and nutrient accumulation. Furthermore, the corn + Crotalaria spectabilis intercropping promoted a greater biomass increase in kg ha−1 and higher nitrogen accumulation in kg ha−1 compared to Feijão guandu anão and Estilosantes Campo Grande.