Resumo O objetivo deste trabalho foi avaliar o potencial de rendimento de grãos de cultivares de soja (Glycine max) modernas submetidas a níveis alto e baixo de manejo de insumos, em diferentes datas de semeadura, na região Sudoeste do Paraná, Brasil. O experimento foi realizado nas safras de 2017/2018 e 2018/2019, no município de Itapejara D’Oeste. Cinco cultivares de soja (BMX Zeus IPRO, BMX Ativa RR, BMX Lança IPRO, NS 5445 IPRO e NA 5909 RG) foram avaliadas em quatro ambientes formados pela combinação de nível de manejo de insumos (alto e baixo) e datas de semeadura (primeira e segunda). O delineamento experimental foi de blocos ao acaso, com três repetições. As características avaliadas foram: potencial de rendimento de grãos (kg ha-1), no estádio fenológico R5; e rendimento de grãos (kg ha-1) e seus componentes, no estádio R8. A cultivar, a época de semeadura e o manejo dos insumos são determinantes para a maximização do potencial produtivo dos grãos. Na primeira data de semeadura, em outubro, a cultivar BMX Zeus IPRO apresenta melhor resposta ao manejo de alto nível, com maior potencial produtivo no estádio R5 (19.682 kg ha-1) e maior produtividade de grãos (8.248 kg ha-1), enquanto NA 5909 RG apresenta os melhores resultados com baixo manejo de insumos.

Abstract The objective of this work was to evaluate the grain yield potential of modern soybean (Glycine max) cultivars subjected to high- and low-input management levels on different sowing dates, in the southwestern region of the state of Paraná, Brazil. The experiment was carried out in the 2017/2018 and 2018/2019 crop seasons in the municipality of Itapejara D’Oeste. Five soybean cultivars (BMX Zeus IPRO, BMX Ativa RR, BMX Lança IPRO, NS 5445 IPRO, and NA 5909 RG) were evaluated in four environments formed by the combination of input management levels (high and low) and sowing dates (first and second). The experimental design was a randomized complete block with three replicates. The evaluated traits were: grain yield potential (kg ha-1), in the R5 phenological stage; and grain yield (kg ha-1) and its components, in the R8 stage. Cultivar, sowing date, and input management are determinant for maximizing grain yield potential. In the first sowing date, in October, the BMX Zeus IPRO cultivar shows a better response to the high level management, with a higher yield potential in the R5 stage (19,682 kg ha-1) and a higher grain yield (8,248 kg ha-1), whereas NA 5909 RG shows the best results with the low input management.

Abstract System fertilization is characterized by partial or total fertilizer application at the predecessor crop; and it can be a viable practice to soybean crop. This study aimed to determine the fertilizer management and fertilizer levels for black oat-soybean cropping system, in high fertility soils and no-tillage system. The field trial was conducted in a bifactorial scheme, consisting of six environments, by combination of locations (Bom Sucesso do Sul - Paraná, Itapejara d'Oeste - Paraná) and fertilization management (all fertilization in black oat; splitting with 50% in black oat and 50% in soybean, all fertilization in soybean), and four fertilizer levels (0, 100, 200 and 300%) defined according to soil analysis and production expected. The evaluated traits were dry mass production, N, P and K nutrient accumulation of straw, dry mass remaining of black oat crop; and plant height, number of pods per plant, thousand grain weight, grain yield for soybean crop. Higher black oat dry mass production was observed at higher fertilization level. The fertilizer anticipation in black oat crop had better performance. Phosphorus and potassium accumulation increased linearly with fertilizer level increase. For N, the highest accumulated value occurred at the 200%, decreasing at the 300% of fertilizer level. The soybean crop had no influence in grain yield considering fertilization management, anticipation or splitting, and fertilizer levels. Thus, the system fertilization can be a viable practice, and favor black oat dry mass production and soybean development.