Hydroponic production of Se-enriched baby leaves of Swiss and its wild ancestor sea beet

The human intake of selenium (Se), which is an essential element in animals and humans,can be increased through the consumption of vegetables that have been biofortified during cultivation.There is increasing interest in wild edible plants (WEPs) due to their positive effects on health. In fact,many WEPs are rich in microelements, vitamins, dietary fibers, and several antioxidant compounds.Among WEPs, sea beet (Beta vulgaris ssp. maritima) is the wild ancestor of Swiss chard (Beta vulgarisvar. cicla). The present study investigated the potential of fortifying Swiss chard and sea beet withSe. The two subspecies were cultivated in a floating system with a nutrient solution enriched withfour concentrations of Se (0, 1, 3, and 5 mg L?1), and the production and quality of the baby leaveswere evaluated. The addition of Se to the nutrient solution resulted in a higher leaf concentration ofthis microelement in both subspecies, with a positive effect on the yield (+20%) and leaf chlorophyllconcentration (+25%) at the Se concentration of 1 mg L?1. The leaf concentration of nitrates wasreduced by the Se treatment in sea beet regardless of the Se concentration (?24%, on average).Selenium biofortification was more effective in sea beet plants than in Swiss chard due to the higherability of the wild species to acquire readily available minerals from the hydroponic nutrient solution.In conclusion, both subspecies accumulated a significant amount of Se without negative effects onyield or leaf quality, thus proving them to be suitable for the production of Se-enriched baby leaves.