Effect of magnesium sulphate biofortification in soilless production of microgreens

This study investigated the effects of five concentrations of magnesium sulphate on selected microgreen species. Six plant species – broccoli, mustard, cress, basil, sunflower and cucumber – were treated with MgSO 4 solutions containing magnesium at concentrations of 0, 10, 20, 30, 40 and 50 mg · L −1 . The content of water-soluble magnesium and calcium, fresh yield, dry matter content, vitamin C, total phenols, flavonoids and antioxidant activity were evaluated in all species. Biofortification significantly increased ( p < 0.05) the Mg content in all tested species without negatively affecting yield. The highest water-soluble magnesium content (after the application of 50 mg · L −1 ) was observed in cucumber (1076 mg · kg −1 FW), while the lowest was found in sunflower (369 mg · kg −1 FW). Compared with the control, the application of 50 mg · L −1 increased the magnesium content in plants by 67% in mustard, 81% in sunflower, 137% in broccoli, 172% in cress, 186% in cucumber and 262% in basil. Furthermore, 50 mg Mg · L −1 significantly enhanced ( p < 0.05) total phenol content, flavonoids, vitamin C and antioxidant activity in broccoli.