Summary of Plant- and Seaweed-Based Extracts Increase Yield but Differentially Modulate Nutritional Quality of Greenhouse Spinach through Biostimulant Action
Biostimulant Extracts Enhance Spinach Yield and Nutritional Quality
Plant biostimulants (PBs) are gaining attention for their ability to improve crop growth and nutritional quality. In this study, biostimulant extracts were shown to increase spinach performance by boosting both yield and functional traits. Three types of PBs were tested on greenhouse-grown spinach: legume-derived protein hydrolysates (PH), Ecklonia maxima seaweed extract, and a mixture of vegetal oils with Ascophyllum nodosum extracts.
How Biostimulants Promote Spinach Growth and Productivity
Foliar applications of PBs at 3 mL L−1, applied weekly during the growth cycle, significantly improved spinach growth. Treated plants showed higher fresh yield, increased dry biomass, and larger leaf area compared with untreated controls. Enhanced chlorophyll biosynthesis, measured via the SPAD index, contributed to healthier, more vigorous plants. These results highlight how biostimulant treatments can naturally support spinach productivity.
Biostimulant Effects on Nutritional Quality
PB applications also improved spinach nutritional content. Total phenols and ascorbic acid levels increased in treated plants, enhancing functional quality. The PH treatment specifically elevated potassium (K) and magnesium (Mg) concentrations without increasing nitrate accumulation, unlike the other PBs. These findings demonstrate that biostimulant applications not only improve growth but also enhance the nutritional value of spinach.
Sustainable Agriculture Advantages of Biostimulant Treatments
Incorporating PBs into vegetable production provides a sustainable strategy for farmers. Using protein hydrolysates, seaweed extracts, or mixed plant extracts allows growers to increase yield, improve nutrient content, and reduce reliance on synthetic inputs. Overall, biostimulant treatments offer a practical and environmentally friendly solution for modern greenhouse cultivation while supporting high-quality, nutrient-rich spinach production.
Publication: Agronomy
