The post-harvest stage of broccoli production requires cold storage to obtain enough days of shelf life. It has been proved that melatonin is useful as a post-harvest agent in fruits and vegetables, including broccoli. In this study, the broccoli heads treated with melatonin have a longer shelf life than the control samples, which was reflected in parameters such as fresh weight, hue angle (expresses color quality), and chlorophyll and carotenoid contents. Treatments with 100 μM melatonin for 15 or 30 min seem to be the most appropriate, extending the broccoli’s shelf life to almost 42 days, when it is normally around 4 weeks. In addition, a study on the possible impact that melatonin treatments in broccoli could have on melatonin intake in humans is presented. The levels of superficial melatonin, called washing or residual melatonin, are measured, showing the possible incidence in estimated blood melatonin levels. Our results suggest that post-harvest treatments with melatonin do not have to be a handicap from a nutritional point of view, but more research is needed.

Melatonin is a new plant hormone involved in multiple physiological functions in plants. Its roles in germination, photosynthesis, growth, flowering, fruiting, and senescence are noteworthy. Most studies have focused on its protective role in different stress situations, both biotic and abiotic. Preliminary data on its promoting role in almond seed germination and seedling growth are presented in this work. The germination-promoting capacity of melatonin was studied in different conditions of light and temperature, with important differences with respect to untreated seeds. The data confirmed that, at specific concentrations, melatonin was capable of stimulating germination, avoiding the stratification process, and therefore, shortening germination times. Furthermore, the melatonin-primed seedlings showed a higher root and aerial growth versus the untreated seeds when light was applied. The possible agronomic impact on the propagation of stone fruit trees was also discussed.