Differentiative assessment between Satureja rechingeri Jamzad and Satureja khuzistanica Jamzad using morphological, phytochemical, and molecular traits

Due to the similarity in appearance and properties of some medicinal plants, it is necessary to identify them more precisely by various methods. Accordingly, in the present study, Satureja rechingeri Jamzad and S. khuzistanica Jamzad were investigated and compared based on morphological, phytochemical, and molecular characteristics. S. rechingeri and S. khuzistanica seeds were collected from Ilam and Lorestan provinces, respectively, and after scientific identification, they were planted in the research greenhouse of the Research Institute of Forests and Rangelands. The seedlings were then transferred to the experimental farm of the mentioned institute based on a t-test (n=3). Several important morphological traits including inflorescence length, inflorescence stem internode length, length and calyx diameter, calyx three-large and two-short teeth length, length and corolla diameter, stamen length, stigma length, length and vegetative organ leaf width, length and leaflet width, stem diameter, plant height, number of main and sub-branches, largest and smallest canopy diameter, and length and reproductive organ leaf width were measured at full flowering stage in the third year of planting. The essential oils (EOs) were extracted from the plants floral branches in the third year of planting through water distillation. The EOs yield was calculated and their compounds were identified using ultra-fast gas chromatography (GC-FID). DNA barcoding and ITS marker were used for molecular studies on these two savory species. The results showed that these two species did not differ significantly (P<0.01) for all the morphological traits examined. 13 common compounds were identified in these two species EO. S. rechingeri and S. khuzistanica EOs contained 88.6% and 89.5% carvacrol, respectively. The EO yeild was obtained 3.3% for S. rechingeri and 3.04% for S. khuzistanica. These two species showed 100% nucleotide similarity with each other and were closely related to S. bachtiarica (98%). On this basis, it is probable that these two species are not only independent species, but can also be different accessions of the same species.