Enhancement of yield and functional quality of Brassica microgreens: Effects of fertilization and substrate

Abstract

Brassica microgreens are rich in bioactive compounds, whose concentrations are influenced by environmental and cultivation conditions. This study evaluates the impact of different substrates and fertigation treatments, including sulfur, on the yield, morphology, and phytochemical profile of radish, red cabbage, white mustard, and red mizuna microgreens. Phytochemicals analyzed included total phenolic compounds (TPC), ascorbic acid (AA), and glucosinolates. Nutrient solutions (NS) increased yield by 30 % compared to distilled water control. Nutrient-rich substrates significantly increased radish and red mizuna yields. Both substrate and fertigation treatments significantly affected morphology. AA and TPC increased significantly (up to 43 %) under restrictive fertigation and substrate conditions. Substrates and NS did not significantly affected glucosinolate levels, but changed their profiles by increasing indole glucosinolates with distilled water. Conversely to AA and TPC, NS improved yield without affecting glucosinolate levels by dilution in higher biomass. Thus, agricultural practices provide valuable tools for modulating the functionality of microgreens.