Agronomic biofortification of common bean (Phaseolus vulgaris L.) cultivated in Oxisol with soil- and foliar-applied zinc

Abstract

Consumption of foods with low zinc (Zn) contents has contributed to the onset of malnutrition and physiological problems in the population. Seeking to improve the nutritional quality of the grains, foliar applications of Zn have been carried out. The aim of this study was to evaluate Zn-EDTA and Zn-Amino as alternatives to ZnSO₄, in foliar application, to improve the nutritional quality of the common bean cultivar ‘BRSMG Madrepérola’. An experiment was carried out in a greenhouse, in a factorial scheme [(3 × 5 + 1) + (1 × 3)], corresponding to three sources, five doses of foliar-applied Zn (2.5, 5.0, 10.0, 15.0 and 20.0 mg dm⁻³), one control, without Zn application and three doses of KCl (0.0, 0.2 and 0.4%) along with the 5 mg dm⁻³ dose of Zn, through foliar application of ZnSO₄, in a randomized block design with four replicates. The foliar application of Zn-EDTA was found to be more effective than other sources in increasing the levels and quantities of zinc and other nutrients in common bean grains. Furthermore, increasing doses of Zn-EDTA resulted in lower phytotoxic effects in common beans when compared to doses of ZnSO₄ and Zn-Amino, with only a minimal reduction in grain yield at the dosage that promoted higher zinc contents in the grains. The foliar application of different doses and sources of zinc leads to increased zinc contents in grains, which could help improve their quality and nutritional value for human consumption, reducing zinc malnutrition.

Keywords:

• Zinc sources
• nutritional quality of food
• increased zinc content in grains

Acknowledgements

The authors gratefully acknowledge HERINGER for providing the fertilizers used in this study. Prof. José João Lelis Leal de Souza for the analysis microchemical map by energy dispersion X-ray fluorescence (EDXRF).

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Funding

This work was supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) (Finance Code 001).