Background: Asafoetida (Ferula assa-foetida L.) is an endangered endemic plant which is widely used in food, cosmetics and pharmaceutical industries. It is necessary to enhance the quantity and quality of its secondary metabolites in order to meet requirements of the industries. Objective: This study investigated the impact of 24-epibrassinolide (EBL) on biochemical traits, essential oil yield and chemical compositions of Ferula assa-foetida in its natural habitat. Methods: We foliar sprayed the EBL at the concentrations of 0, 0.1, 0.5 and 1 µM with three times during a week at fully matured leaves phase. One month after treatments application, leaf sampling and gum gathering of the plants was done and the mentioned parameters were measured. Results: ANOVA results indicated that 1 µM EBL showed the best results for chlorophyll a, b, total chlorophyll, carotenoids, reduced sugar and protein contents (17.77, 13.08, 31.57, 7.50, 40.45 and 0.34 mg/g FW). The main components of the essential oil are α-pinene (8.82 %), β-pinene (11.57 %) and myrcene (1.12 %) that showed a significant increase at 1 µM of EBL. Although, EBL at 0.5 µM was proved to be the best treatment for leaf total phenol content (79.37 mg/g FW) and sulfurous compounds such as: (E)-1-propenyl sec-butyl disulfide (51.48 %), bis (1-methyl propyl) disulfide (0.9 %) and n-propyl sec-butyl disulfide (0.41 %). The highest amount of flavonoids (146.18; 162.56 mg/g FW) and essential oil yield (7.91 %; 8.16 %) were obtained at 0.5 and 1 µM EBL concentrations, respectively compared to the control (6 %). Conclusion: Our results indicated the promising and positive effects of EBL, as an environmental friendly strategy, to improve oleo-gum quantity and quality.

Background: Satureja khuzestanica is an endemic medicinal plant that widely distributed in the northern Khuzestan and southern Lorestan provinces of Iran. Objective: In this study, simultaneous effects of methyl jasmonate (MeJA) and salinity on morpho-physiological parameters and minerals contents in S. khuzistanica were studied. Methods: Different salt levels (0, 3, 6 and 9 dS/m) were applied during growth period for one month. MeJA spraying at 0, 60 and 120 µM concentrations performed three times for one week. Samples were taken during flowering stage. Results: The results showed that MeJA × salt interaction had significant effects on all morpho-physiological and biochemical parameters of S. khuzestanica (P < 0.01). The highest stem length, root length, fresh and dry weights were observed at 60 and 120 µM MeJA without salt. The amounts of chlorophyll, N, P, K⁺, K⁺/Na⁺, Ca²⁺ and Mg²⁺ had significant reductions with increasing salt levels. The highest amounts of these parameters were observed at 60 µM MeJA without salt. There were significant enhancements in total phenol, antioxidant activity, proline, sugar and Na amounts with increasing salt levels. The highest content of total phenol and antioxidant activity was induced at 60 µM MeJA × 6 dS/m salt (2.22 and 50.23 %, respectively). The 9 dS/m salt treatment at 60 µM MeJA had the highest sugar (1.69 mg/g) and proline (0.29 mg/g) contents. Conclusion: Totally, 60µM MeJA concentration caused the best performance of savory under salt stress. Therefore, MeJA application can be helpful to alleviate negative effects of salt in S. khuzistanica.