Biofortification with copper nanoparticles (Nps Cu) and its effect on the physical and nutraceutical quality of hydroponic melon fruits

Currently the use of nanoparticles is having an impact on agricultural production. There is evidence that copper nanoparticles have a strong impact on the growth and development of different crops. Biofortification specifically with (NPs Cu) improves the nutritional quality of food and its consumption has a positive influence on the health of humanity. The objective of this study consisted in evaluating the foliar application of copper nanoparticles (NPs Cu), on the weight of the fruit, nutraceutical quality and concentration of copper in melon fruit pulp. The treatments consisted of five doses of Cu NPs: 0, 1.8, 3.6, 5.4, 7.2 and 9.0 mg L ^-1 sprinkled foliarly. The variables evaluated were fruit weight, polar and equatorial diameter, firmness, total soluble solids, bioactive compounds and copper content in melon pulp. The results obtained indicated that the foliar application of NPs Cu, improved the physical and nutraceutical quality and the concentration of Cu in melon fruits. The highest weight and the best diameters of the fruit were obtained with the highest concentrations of NPs Cu (7.2 and 9.0 mg L^-1 ). The concentration of 3.6 mg L^-1 Cu NPs presented the highest antioxidant capacity with a value of 117,713 mg equiv. Trolox * 100 mg ^-1 PF, and higher content of phenols with 243.68 mg ac. gallic / 100 g FP, exceeding the concentration of 1.8 mg L ^-1 by 39% and the control treatment by 48%. The 3.6 and 5.4 mg L^-1 treatments obtained the highest amount of flavonoids with values of 149.903 and 148.29 mg QE / 100 g ^-1 FP, respectively. Regarding the copper concentration in the melon fruit pulp, the 9.0 mg L^-1 treatment presented the highest concentration with a value of 5.39 mg kg ^-1 PS; The results show that, statistically, there is a correlation between the copper nanoparticles and the phytochemical variables in melon fruits. It is concluded that the use of Cu NPs can be an alternative to enrich melon fruits, and could help to solve the copper deficiency in the diet of the population.