OICC Press International Journal of Recycling of Organic Waste in Agriculture 2251-7715 13 5 2024 08 10 Effect of vermicomposting plant residues on phytochemical properties of Zarrin-giah (Dracocephalum kotschyi Boiss.) 10.57647/ijrowa-9ggb-4114 EN Maedeh Bohlouli Department of Horticulture, College of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran 0009-0005-5259-5573 Hossein Ali Asadi-Gharneh Department of Horticulture, College of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran 0000-0003-4880-2443 Elham Chavoshi Department of Soil Science, College of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran 0000-0003-3141-3820 Nafiseh Zamindar Department of Food Science and Technology, Collage of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran 0000-0001-9098-4282 Journal Article 2024 08 10 Purpose: This study was conducted to evaluate whether vermicompost production from various plant residuals could improve the biomass and essential oil properties of Zarrin-giah (Dracocephalum kotschyi Boiss.). Method: In this experiment, different types of vermicompost were prepared from five residual biomasses of chamomile, madder, licorice, valerian, and pistachio with cow dung and Eisenia fetida worms. Subsequently, Zarrin-giah plants were treated with 0, 10%, and, 20% of vermicompost. After 176 days, plants were harvested, and the influence of treatments on Zarrin-giah biomass and phytochemical properties was evaluated. Results: The use of vermicompost improved plant biomass and phytochemical traits. The highest Zarrin-giah essential oil contents were noted with 20% vermicompost derived from madder and pistachio waste. Neral, α-pinene, geranial, geranyl acetate, and limonene were identified as the main chemical compounds, with the best results observed at 10% vermicompost amendment. Samples amended with 10% and 20% vermicompost from pistachio waste and 10% vermicompost from valerian waste had the highest antioxidant activity (displaying the lowest IC50 values of 19.29, 19.26, and 20.25 μg/mL, respectively). Vermicompost derived from licorice waste improved Zarrin-giah biomass, with yields of 29.05 and 27.93 g/plant at 20% and 10%, respectively. Moreover, significant differences in substrate nutrient recycling and electrical conductivity were observed among various treatments. Conclusion: High electrical conductivity levels indicate a salinity issue in vermicomposts derived from pistachio and madder waste. Nonetheless, these treatments positively affected substrates, enhancing the antioxidant activity and essential oil content of the medicinal plant Zarrin-giah, which were the primary objectives of this research. Highlights:  High electrical conductivity in vermicompost increases the chemical compounds in Zarrin-giah Vermicompost of different plant residues improve Zarrin-giah phytochemical properties. Limonene, a-Pinene, Neral, Geranial and Geranyl acetate were identified as important compounds. Vermicompost of licorice waste in all stages support the Zarrin-giah biomass There is a direct relationship between Essential oil content and Zarrin-giah biomass. Zarrin-giah is a native Iran's plant and it is in extinction.