Effect of nutrient strength and Trichoderma bio-priming on the nutritional composition of hydroponically grown mustard microgreens

Microgreens are nutrient-dense functional foods whose composition can be modulated by cultivation practices. The present study evaluated the combined effects of hydroponic nutrient strength and Trichoderma seed biopriming on the nutritional and mineral composition of mustard (Brassica juncea L.) microgreens. Three hydroponic nutrient regimes, pure water, half-strength, and full-strength nutrient solution, were tested in combination with three strains of Trichoderma viride. The results revealed significant (p ≤ 0.05) improvements in proximate composition, including crude fiber, carbohydrate, protein, fat, and calorific value, with increasing nutrient strength. Full-strength nutrient solution (N3) yielded the highest protein (8.47%), fat (0.98%), and calorific content (29.24 J 100 g⁻¹). Among biopriming treatments, Trichoderma strain T2 showed a notable increase in protein (7.32%) and mineral uptake compared to T1 and T3. The interaction of N3 × T2 recorded superior values for protein (8.92%), fat (1.04%), and potassium (0.62%), along with enhanced calcium (0.190%) and zinc (57.5 ppm). These findings suggest that both nutrient strength and Trichoderma biopriming act synergistically to enhance the nutritional quality of mustard microgreens. Optimizing these practices may provide a sustainable strategy to produce microgreens with improved health-promoting properties.