NPK fertilization for the first years of physic nut cultivated in two regions.

The physic nut is an oilseed plant that has stood out as an alternative source for biodiesel. However, using it in this way requires determining the edaphoclimatic conditions and adequate fertilization to guarantee maximum productivity. This study objectived to evaluate and establish adequate rates of Nitrogen (N), Phosphorus (P), Potassium (K) to maximize the growth and productivity of physic nut in two edaphoclimatic conditions. Two experiments were performed over two consecutive years, one under Quartzarenic Neosol in the municipality of Diamantina and the other under Red-Yellow Latosol in the municipality of Governador Valadares. The treatments comprised rates of N: 0, 25, 50, 100 kg ha⁻¹; P: 0, 35, 70, 140 kg ha⁻¹; and K: 0, 40, 80, 160 kg ha⁻¹. Plant growth was evaluated every 30 days until flowering. Seed and oil productivity was also assessed, with one harvest in Diamantina and two harvests in Governador Valadares. The edaphoclimatic condition of Governador Valadares was a determining factor in providing greater growth and productivity of the physic nut when compared to that of Diamantina. The application of N rates was unnecessary for the growth and productivity of the physic nut in Diamantina. Thus, phosphate fertilization was unnecessary in Governador Valadares and potassium fertilization was unnecessary for both regions. In Diamantina, 84 kg ha⁻¹ and 87 kg ha⁻¹ of P is recommended for growth and maximum productivity, respectively. Whereas, in Governador Valadares, 49 kg ha⁻¹ and 55 kg ha⁻¹ of N is recommended for growth and maximum crop productivity, respectively. [ABSTRACT FROM AUTHOR]