Resposta e eficiência de uso do fósforo em cultivares de soja em solos do cerrado

Abstract

Given the importance of phosphorus for soybean productivity and its limited availability as a resource, it is essential to identify genotypes that are more efficient in absorbing this nutrient. Therefore, this study aimed to evaluate the response and efficiency of phosphorus use in soybean cultivars subjected to different levels of phosphate fertilization in Cerrado soil, using biometric parameters obtained during the vegetative phase. The experiment was conducted at the IFPI experimental farm - Uruçuí campus, in a greenhouse, using a completely randomized design in a 3 x 8 split-plot arrangement. The three treatments provided different phosphorus conditions (0 kg ha⁻¹, 100 kg ha⁻¹, and 200 kg ha⁻¹), and the plots corresponded to the eight cultivars, with five replications of each treatment for each cultivar. The cultivars evaluated were: Neo 790 IPRO, Neo 802 I2X, Neo 820 IPRO, DM 78IX80 I2X, DM 8085 IPRO, DM 82I78 IPRO, TMG 22X83 I2X, and ÍMPETO I2X. The parameters evaluated were: plant height (PH), shoot fresh weight (SFW), root fresh weight (RFW), total fresh weight (TFW), shoot dry weight (SWW), root dry weight (RDW), and total dry weight (TDM). Among the cultivars evaluated, Neo 820 IPRO and Neo 802 I2X stood out, showing greater efficiency in phosphorus absorption and use at different availability levels. The results highlight wide genetic variability among the materials and reinforce the potential of using more efficient genotypes as a strategy to optimize phosphorus utilization in Cerrado agricultural systems