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

Abstract

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.

Keywords:

• Biodiesel
• Jatropha curcas
• mineral nutrition
• oilseed
• physic nut

Acknowledgments

The Minas Gerais Research Support Foundation (Epamig) from the Norte de Minas Technological Center, in Nova Porteirinha, Minas Gerais state, for the supply of physic nut seeds. The Federal University of the Jequitinhonha and Mucuri Valleys for providing the necessary infrastructure for experimenting.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The Foundation for Research Support of the State of Minas Gerais (Fapemig) and the National Council for Scientific and Technological Development (CNPq) for financial support. The Coordination for the Improvement of Higher Education Personnel (Capes) for the master’s scholarship.