Comparative LC-MS-based metabolite profiling of the Peppermint, Rosemary, Savory, and Thyme extracts and their potential role in germination and early growth of and .

Seed germination is a critical stage in crop growth and is often limited by various biotic and abiotic factors that hinder plant establishment. Seed priming is a pre-sowing treatment that prepares seeds, enhancing the potential for more vigorous seedling emergence. This study aimed to explore the effects of leaf extracts from Peppermint, Thyme, Rosemary, and Savory, both individually and in combination, as seed priming agents on the early germination stages of and , which were grown in pots in a greenhouse. In the experiment, seeds of and were soaked in leaf extracts at concentrations of 10%, 20%, and 30%, and treated with the fungicide mixture of carbendazim and iprodione at a rate of 2%. A completely randomized design was utilized, with three replications, featuring 20 seeds planted in each pot. The main compounds identified in the Peppermint, Rosemary, Savory, and Thyme leaf extracts through LC-MS analysis included caryophyllene oxide, β-caryophyllene, rosmarinic acid, cinnamic acid, caffeic acid, and limonene. The results showed that the application of these leaf extracts positively influenced key indicators, such as emergence and growth traits. Among the priming agents tested, the 10% extracts of Rosemary and Savory significantly improved germination and emergence rates of and ( < 0.05). The findings indicated a germination percentage of 100% for and 76.7% for , along with seedling lengths increasing by 30% and 20%, seed vigor indices rising by 30% and 15.3%, and leaf numbers of 8 and 4, respectively. While lower extract concentrations also enhanced early growth parameters such as germination percentage, seedling length, and vigor index, maximum improvement was observed with the 10% extracts of Rosemary and Savory. Therefore, these 10% extracts can be effectively used to promote seedling establishment and growth in and under pot conditions, demonstrating competitive efficacy compared to the commercial use of carbendazim + iprodione.