Triple superphosphate provides high yields of soybean genotypes in the Brazilian Cerrado

Abstract

Soybean is currently the main crop in national agribusiness. Phosphorus is a limiting nutrient in obtaining high yield, especially in the soil conditions of the Brazilian Cerrado. Thus, the objective was to analyze the effect of triple superphosphate doses on the yield of soybean genotypes under Cerrado conditions. The study was conducted in Mineiros, GO, Brazil. A randomized block design was used, in a 4x5 factorial scheme, corresponding to four soybean genotypes (AS3680, NA5909, NA7337 and TMG1180), in five levels of phosphorus (0, 100, 200, 300 and 400 kg ha-1 of P2O5) using Triple Superphosphate (41% P2O5 and 9% Ca), in 4 repetitions. The variables related to yield were evaluated at 146 days after sowing. Statistical analyzes were performed on the R Core Team (2019). The study revealed a significant interaction (p≤ 0.05) between soybean genotypes and phosphate doses, in addition to the significance (p≤ 0.05) in the main effects. The regressions were adjusted and estimated with optimal points close to 100 kg ha-1 of P2O5 for the different characters. Positive and negative correlations and their trends were considered among the variables for each soybean genotype, in addition to grouping the interaction of factors. The characters with the greatest contribution to raising yield levels were the thousand grain mass, plant stand and pods per plant. Using triple superphosphate as a phosphate source, it is recommended to grow the AS3680 genotype, which showed the highest yield (91.57 bag ha-1) with a dose of 95.65 kg of P2O5 ha-1, corresponding to 21.57% increments in yield.