Efeito da densidade populacional em cultivares de soja

Abstract

Soybean is currently the main oilseed produced in Brazil. One of the challenges of genetic improvement programs is to obtain greater production in the same amount of area, so one of the factors that can contribute to this is the study of different sowing densities. Thus, the objective was to evaluate the yield components of soybean cultivars submitted to different sowing densities. For that, eight genotypes (Brasmax Fibra (64I61) IPRO RR2®, Brasmax Compacta (65I65) IPRO RR2®, Brasmax Ponta (7166) IPRO RR2®, Brasmax Icon (68I70) IPRO RR2®, Brasmax Potência RR1®, DM 66I68 RSF IPRO RR2®, M6210 IPRO RR2® and M6410 IPRO RR2®) and three sowing densities were used, one ideal and the others below and above the ideal, in three different locations, Cafelândia - PR, Maracaju - MS and Dourados - MS, during the 2020/21 harvest. The following characteristics were evaluated in five plants in the useful area of each plot: number of pods per plant, by directly counting the total number of formed pods; mass of 100 grains, using eight subsamples of 100 grains, which were weighed on an analytical balance with a sensitivity of 0.001g; and yield, determined in kg ha-1 by threshing all the plants in the plot. Data were subjected to analysis of variance and, when significant, analyzed, tested and grouped using the Scott Knott test. It was concluded that smaller plant populations do not affect yield, due to the compensation obtained by the greater number of pods per plant. The yield, mass of 100 grains and number of pods per plant, vary according to the cultivar used, due to their different adaptations to environments.