Journal of Plant Process and Function

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In order to investigate the effect of different levels of water stress on Satureja hortensis, a completely randomized design (CRD) with four replications was carried out in the greenhouse of Yazd University in 2014. The water stress treatments including 100, 75, 50 and 25 Percent of field capacity (FC) were applied. The results showed that water deficit stress significantly (p<0.01) decreased plant height, canopy cover volume, canopy cover surface, shoot dry weight and root dry weigh, root thickness as well as soluble sugars content. Also, proline, chlorophyll content and root length significantly increased under drought stress. The maximum amount of proline, a, b and total chlorophyll and root length was observed in 25% of field capacity. Maximum plant height, crown volume and leaf area was obtained at 75% of field capacity. The shoots and roots dry weight of and crown area was observed in plant treated at 100% of field capacity. The overall results of this study showed that S.hortensis with can be adapted to drought stress by using some avoidance mechanisms such as reduced plant height, plant volume, surface and crown diameter, shoot and root dry weight, root thickness and increasing of chlorophyll contents and proline.

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The objective of this study was to determine the effects of lead (Pb) exposure on bioaccumulation, growth, and tolerance mechanisms in summer savory (Satureja hortensis L.). Plants were subjected to different levels of Pb concentrations including 0 (control), 5, 10, 25, 50 and 100 mg L^-1 in growing medium. Pb treatment led to significant increase in root and shoot Pb content. Calculation of BF, TF and TC revealed that Pb preferably accumulated in roots of S. hortensis and root to shoot transport was effectively restricted. Pb toxicity negatively affected plant growth as indicated by significant decrease in plant dry weight as well as roots and shoot length. Pb stress resulted in significant decrease in chlorophyll-a, chlorophyll-b and total chlorophyll content, whereas proline, soluble and reducing carbohydrates and anthocyanin content significantly increased as a result of Pb exposure. Specific activity of antioxidant enzymes including catalase and ascorbate peroxidase continuously increased as concentration of Pb in growing medium elevated. Based on our findings, due to high potential for Pb accumulation in root, S. hortensis may offer a feasible tool for phytostabilization purposes in mildly Pb contaminated soils.