Effects of Phytohormones on Morphological and Biochemical Traits in Mungbean Sprouts

Phytohormones affect morphological traits and the accumulation of secondary metabolites in plants. In mungbean, the effect of phytohormones on physical traits has been studied, but the impact on biochemical traits remains unknown. To investigate biochemical changes in response to hormones (6‐benzylaminopurine (6‐BA), ethephon (ETH), and 2,4‐dichlorophenoxy acetic acid (2,4‐D)), the content of secondary metabolites was measured using ultra‐performance liquid chromatography (UPLC) with various hormone concentrations. After treatment with the three hormones, the thickness of the hypocotyl increased compared with the control, while the lengths of the hypocotyl and root decreased. In the 6‐BA and 2,4‐D treatments, lateral roots were not detected. In terms of total phenolic compounds, the highest content was observed with the 10 mg/L hormone treatment, and the phenolic compound content decreased as the hormone treatment concentration increased. Total flavonoid content decreased as the treatment concentrations of 6‐BA and ETH increased. The highest total flavonoid content was observed in the treatment with 10 mg/L of 2,4‐D. The antioxidant activity decreased as hormone treatment concentrations increased. Seventeen compounds were quantified using the UPLC system. While phenolics are generally decreased with phytohormone treatment, the content of isoflavonoids significantly increased. Genistein increased in all phytohormone treatments. With ETH and 2,4‐D treatments, the contents of glycitin and coumestrol elevated significantly. These findings suggest that phytohormone treatments, especially at optimal concentrations, can improve the morphological and nutritional quality of mungbean sprouts. Furthermore, isoflavonoid accumulation enhanced by cytokinin, ethylene, and auxin application may contribute to the functional value of mungbean sprouts and provide insights into the targeted use of phytohormones in mungbean sprout cultivation.