Foliar Application of Iron and Zinc Affected Growth, Mineral Content and Essential Oil Profile in Origanum dubium Boiss
Journal
Journal of Soil Science and Plant Nutrition
Date Issued
November 28, 2025
Author(s)
DOI
10.1007/s42729-025-02847-5
Abstract
Medicinal and aromatic plants production has lately attracted considerable research interest in the agricultural sector and in a series of industrial applications. The Origanum genus comprises different plant species that have district odors, flavors and biological properties. The objective of the present study was to evaluate any stimulatory and biofortification role that foliar applications of iron and zinc might have on Origanum dubium plant. The endemic to Mediterranean region O. dubium plants were grown in hydroponics, while iron (1.8 mM and 10.8 mM Fe) and zinc (1.4 mM and 10.4 mM Zn) foliar treatments were applied (4 times) during the cultivation period. The effects on features such as plant development, physiology, antioxidant capacity, nutrient accumulation, and essential oil (EO) yield and profile were evaluated. Foliar application with Fe at 1.8 mM increased the fresh and dry weight of O. dubium, decreased oxidative stress by decreasing the lipid peroxidation and hydrogen peroxide levels, and slowed down the EO terpene synthesis to form carvacrol. In contrast, the high Fe levels of 10.8 mM and both Zn levels stimulated the plants total flavonoids and antioxidant activity as they had greater oxidative stress and increased enzymatic catalase activity. Both foliar Fe levels increased the nitrogen and potassium accumulation in plants, while Fe content was accumulated more only after 10.8 mM Fe application. Foliar Zn stimulated the zinc accumulation and decreased the copper levels in plants. Essential oil content decreased with the foliar Zn application at 10.4 mM, while the 1.74 mM Zn application decreased specific compounds such as; trans-sabinene hydrate and γ-terpinene content but stimulated the carvacrol content. Biofortification with minerals is an important strategy to improve the nutritive value and biological properties of O. dubium plants and their EOs composition.