Adubação potássica e fosfatada na sucessão cártamo e soja

Abstract

Soybeans is a widely cultivated species and is considered of primary importance, however, due to the successive exploitation of the soil, the use of conservation practices is recommended, especially in the dry season, in this context, succession culture may represent an alternative for management these areas. Therefore, the objective was to evaluate the performance of safflower crop under phosphorus and potassium rates and the residual effect on soybean crop. The experiment was carried out in two periods: The safflower was sown in March 2018 in a randomized block design with 4x4 factorial scheme, with 4 replications. The treatments consisted of 4 rates of potassium (0, 30, 60 and 120 kg ha-1 of K2O) and 4 doses of phosphorus (0, 30, 60 and 120 kg ha-1 of P2O5) superficially distributed after sowing. In the summer harvest, soybean was sown with parcel reuse. Biometric components were evaluated: chlorker falker index; leaf area index; plant height and first branch / pod; number of branches and stem diameter. Productive characteristics: number of grenade heads / pod, undeveloped head and grain per head/ pod; productivity and macronutrient content. Ether extract, crude protein and dry matter were evaluated only in safflower crop. Data were subjected to analysis of variance and when significant regression at 5% probability. Height was influenced in both crops by the applied rates, with interaction for safflower and effect of P doses for soybean. Crop yield was not influenced by rates. Potassium and phosphate fertilization in succession systems on soils with built fertility did not increase crop yield.