Selenium biofortification of three wild Species, Rumex acetosa L., Plantago coronopus L., and Portulaca oleracea L., grown as microgreens

Foliar spray with selenium salts can be used to fortify tomatoes, but the results vary in
relation to the Se concentration and the plant developmental stage. The effects of foliar spraying with
sodium selenate at concentrations of 0, 1, and 1.5 mg Se L?1 at flowering and fruit immature green
stage on Se accumulation and quality traits of tomatoes at ripening were investigated. Selenium
accumulated up to 0.95 g 100 g FW?1, with no significant difference between the two concentrations
used in fruit of the first truss. The treatment performed at the flowering stage resulted in a higher
selenium concentration compared to the immature green treatment in the fruit of the second truss.
Cu, Zn, K, and Ca content was slightly modified by Se application, with no decrease in fruit quality.
When applied at the immature green stage, Se reduced the incidence of blossom-end rot. A group
of volatile organic compounds (2-phenylethyl alcohol, guaiacol, (E)-2-heptenal, 1-penten-3-one and
(E)-2-pentenal), positively correlated with consumer liking and flavor intensity, increased following
Se treatment. These findings indicate that foliar spraying, particularly if performed at flowering
stage, is an efficient method to enrich tomatoes with Se, also resulting in positive changes in fruit
aroma profile.