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Secondary metabolites, especially essential oils are of the widely used phyto-chemicals for various purposes. In this regard, numerous studies have been reported on profile of these reputed metabolites in medicinal and aromatic plant (MAPs) species. Of the substantial family of the MAPs, Lamiaceae is of the reputed group with a notable number of plant species. Regarding the species of this group, sage (Salvia officinalis) and rosemary (Rosmarinus officinalis) are of the well-known and widely-studied species. Herewith the current study, we profiled the essential oil composition in leaves of both species. Accordingly, the analysis revealed that camphene (29.40%), 1,8-cineole (37.26%), camphor (13.48%), borneol (3.69%), trans-caryophyllene (5.42%), and α-thujone (5.78%) were of the predominant compounds identified for S. officinalis, whilst camphene (22.45%), 1, 8-cineole (35.36%), linalool (3.67%), camphor (10.80%), cyclohexane,(1-methylethylidene) (3.09%), α-fenchyl alcohol (3.03), 2-cyclohexen-1-one, 2-methyl-5-(1methylethenyl) (2.12%), and endo-bornyl acetate (4.50%) were of the principal components in leaves of R. officinalis.The next studies on the relevant species might be focused on the biological activity of the essential oils.

Water stress is one of the most critical threats to the growth and productivity of plants and is one of the most studied topics in agricultural sciences. In order to enhance the tolerance of plants to water stress conditions, synthetic fertilizers have been widely used in the field. However, due to their toxic effects, recent reports have focused on organic options. In this study, the effects of liquid vermicompost applications (25, 50, 75, and 100%) on the agronomic attributes, phenolic compounds, and essential oil compounds of basil plants exposed to drought stress conditions were investigated. Accordingly, water stress critically reduced the factors of plant height, plant fresh weight, root fresh weight, leaf length, and leaf diameter. On the other hand, vermicompost applications significantly affected all of the parameters considered, except the leaf length of well-watered basil plants. However, a two-way ANOVA analysis revealed that the interactions of water stress and vermicompost were significant on root length and root fresh weight. Regarding the essential oil compounds, the contents of humulene, anethol, eucalyptol, estragole, bisabolene, germacrene, and caryophyllene were quantified. Estragole was determined as a major component by 85–90%. The results revealed that the highest estragole content was determined in the 25% vermicompost + water stress, water stress, and control groups. Of the major phenolic compounds, caffeic acid decreased as a result of water stress conditions but increased with vermicompost treatments. The rosmarinic acid content increased during water stress conditions, attaining the highest content at 25% via the vermicompost and water stress interaction. In general, the 25% and 50% vermicompost applications increased the content of phenolic compounds in plants under either well-watered or stress conditions.

In nature, plants are constantly challenged by an array of drought episodes, which critically affect the distribution of the plants. The drought episodes might occur recurrently, so the plants endure drought by adjusting and shifting their metabolisms. The impacts of subjecting plants to drought stress have been widely investigated, but reports on how reiterated drought stress affects the plants are limited. The present study was designed to investigate the response of lavender, a reputed medicinal and aromatic plant, against single drought, recovery and reiterated drought stress at greenhouse conditions. In this regard, the experimental design was based on three cycles of 11 days of drought by withholding water, followed by subsequent periods of 6 days of recovery, and then double-stressed and single-stressed periods. As expected, the present findings revealed that single stress decreased the fresh and dry weights of the leaf, stem and root. Reiterated drought stress caused critical reductions in the fresh weight of the leaf, stem and root, while the dry weight of stem and root were not significantly affected. Of the estimated traits, only the dry weight of leaf increased with reiterated drought stress. The mineral status of the leaves was adversely affected with single stress, but the effects of recovery and reiterated stress were not in accordance with the improvement in water contents of the leaf and soil. Regarding essential oil compounds, eucalyptol, camphor and endo-borneol were predominant. Single and reiterated drought stress increased camphor percentage, while recovery and full irrigation decreased the percentage. Endo-borneol was decreased under single stress, but reiterated stress increased the percentage of the compound. Considering the phenolic acids, stressed and non-stressed groups were well discriminated and hence, phenolic acids might be useful as good indicators of the stress response in lavender.

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