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In this research, plant morphology and pollen micromorphology of 14 populations of 3 species belonging to two sections Plethiosphace and Hemisphace of Salvia genus in Iran were studied. In the morphological study 25 quantitative and qualitative characters were investigated and the results clearly separated the species into two groups. The pollen grains from the herbarium specimens were prepared by acetolysis method and then 4 quantitative characters were examined by light microscopy. Data was processed by principal component analysis method. Results indicated that although the pollen grains in the section were comparatively homogenous and all of them were 6-colpate with reticulate ornamentation, a considerable variation in the quantitative characters studied turned out to exist. However among the characters studied, equatorial and polar diameters of pollen grains were the most significant and based on these characters the members of these sections can be divided into two groups.

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Pennyroyal (Mentha pulegium L.) from the Lamiaceae family is a medicinal plant which has great antioxidant properties. Environmental stresses such as drought can result in changes in the activity of antioxidant enzymes and the content of some biochemical factors in plants. In this investigation, the effects of drought stress on the activity of supe-roxide dismutase, ascorbate peroxidase, catalase, peroxidase, malondialdehyde and soluble sugars content in pennyroyal shoots and roots were evaluated. To create the water deficit, 24-day seedlings of pennyroyal were placed in 1/2 strength Hoagland solution, containing PEG 6000 (0 and 5% (w/v)) for 24 hours. The results showed that drought stress incr-eased catalase activity and lipid peroxidation and decreased superoxide dismutase and peroxidase activity of the shoots. On the other hand, the activity of catalase and peroxidase increased in the roots. Ascorbate peroxidase activity showed no significant difference in the shoots and the roots. Moreover, drought stress significantly increased the amount of so-luble sugars of glucose, galactose, xylose and rhamnosus in the shoots. Therefore, the increased activity in antioxidant enzymes as well as the amount of soluble sugars under drought stress might be a sign of tolerance of M. pulegium under low levels of drought.

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The Moldavian dragonhead (Dracocephalum moldavica L., Lamiaceae) is an annual medicinal plant with beneficial nutritional sources that plays important roles in human and animal feed. Nanoparticles and cold atmospheric plasma increase biochemical compounds in plants. In this study, the effects of copper nanoparticles and cold atmospheric plasma on biochemical indices of the medicinal plant Dracocephalum moldavica were investigated. Moldavian dragonhead plants were subjected to four doses of copper nanoparticles (0, 25, 50 and 75 mgl^-1) and cold atmospheric plasma at three durations (zero, 20 and 30 s). The results showed that cold atmospheric plasma significantly increases the essential oil percentage, while it decreases the amount of flavonoid content and activity of catalase and peroxidase enzymes. Cold atmospheric plasma (20 s) showed significant positive impact on essential oil content, while different time duration (20 and 30 s) did not show a significant impact on other traits. Lower doses of copper nanoparticles (25 and 50 mgl^-1) showed positive impacts on measured traits, while 75 mgl^-1 dose negatively affected the measured traits and functioned as a heavy metal. The cold atmospheric plasma and copper nanoparticles interactions indicated that cold atmospheric plasma had an incremental effect on the improvement of measured traits and increased the effect of copper nanoparticles. In conclusion, the results showed that copper nanoparticles with 25 mgl^-1 dose along with cold atmospheric plasma with 20 s duration had significant positive effects on the improvement of biochemical indices of Dracocephalum moldavica.