Shima Alaei; Nasser Mahna
Abstract
Glycine betaine (GB) plays a crucial role in plants and in their response to abiotic stress. This experiment was conducted to evaluate the application of glycine betaine (GB) and its ability to alleviate the effects of salinity stress (SS) on fruit yield and ion accumulation in strawberry (Fragaria × ...
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Glycine betaine (GB) plays a crucial role in plants and in their response to abiotic stress. This experiment was conducted to evaluate the application of glycine betaine (GB) and its ability to alleviate the effects of salinity stress (SS) on fruit yield and ion accumulation in strawberry (Fragaria × ananassa Duch cv. Paros). Three levels of SS (0, 20, and 40 mM NaCl) and GB (0, 5, 10 mM) were used on the plants in a greenhouse experiment. The results indicated that increasing the salinity level reduced the yield and altered the dynamism of ion accumulation. Leaf area, relative water content (RWC), leaf fresh weight, and yield decreased under salinity stress (36.7%, 9.2%, 28%, and 41%, respectively), especially at 40 mM NaCl. Under SS, there was an increase in Na content of the roots, fruits, and leaves (78%, 54%, and 78%, respectively) as well as in K content of the fruits (50%), but with a decrease in the K content of the leaves (29%) and the roots (25%), and P content of the leaves (55%). Overall, salinity increased the Na content, but reduced the K/Na ratio. Salinity and glycine betaine interactions had a significant effect on the Na content of the roots and leaves, the K content in the leaves, and K/Na ratio in the leaves and roots. At 40 mM NaCl, using 10 mM GB reduced the leaf and root Na content by 22% and 30%, respectively. Although the application of exogenous GB on strawberry changed the pattern of ion accumulation, it was not effective in diminishing the adverse effects of salinity stress on strawberry plants cv. ‘Paros’.
Shima Alaei
Abstract
Dracocephalum moldavica L. is an annual species of Lamiacea family whose essential oil is widely used in medicinal, food, cosmetic and health industries. Drought stress is a major factor limiting plants growth and yield. The main objective of this study was to evaluate the influence of irrigation regime ...
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Dracocephalum moldavica L. is an annual species of Lamiacea family whose essential oil is widely used in medicinal, food, cosmetic and health industries. Drought stress is a major factor limiting plants growth and yield. The main objective of this study was to evaluate the influence of irrigation regime on essential oil content and composition of D. moldavica L. The Irrigation regimes were 100%, 85%, 75% and 55% of field capacity (FC). The results showed that 53 essential oil components were identified in different irrigation regimes. Thirty-six, twenty-two, twenty and thirty components were identified at 100%, 85%, 75% and 55% of FC, respectively. The amounts of identified components were 99.4%, 96.6%, 97.8% and 99.9% at 100%, 85%, 75% and 55% of FC, respectively. The highest of main components were geranyl acetate, geraniol and geranial in all the irrigation regimes. The amount of oxygen-containing monoterpenes of essential oil were 81.6%, 94.5%, 91.8% and 92.0% at 100%, 85%, 75% and 55% of FC, respectively. Our results showed that essential oil content increased significantly by 3.4%, 13.8% and 27.6% at 85%, 75% and 55% of FC, respectively. Furthermore, the amount of oxygen-containing monoterpenes of D. moldavicum increased by 15.8%, 12.5% and 12.7% at 85%, 75% and 55% of FC, respectively, but oxygen-containing sesquiterpenes decreased by increasing the level of drought. In conclusion, our results indicated the advantage of drought for increasing essential oil content and oxygen-containing monoterpenes (OM), especially geranyl acetate, geraniol and geranial in D. moldavica.
