Borzou Yousefi; Roya Karamian
Abstract
White savory (Satureja mutica Fisch.) is an oil-bearing plant with applications in traditional medicine, pharmaceutical industries, and food additives in homemade dishes. The current research comprised a greenhouse experiment in a factorial arrangement based on a completely randomized design (CRD). It ...
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White savory (Satureja mutica Fisch.) is an oil-bearing plant with applications in traditional medicine, pharmaceutical industries, and food additives in homemade dishes. The current research comprised a greenhouse experiment in a factorial arrangement based on a completely randomized design (CRD). It included four salinity levels (0, 50, 100, and 150 mM NaCl), two salicylic acid (SA) levels (0 and 2 mM), and three replicates. By increasing the NaCl concentration, the content of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid significantly declined. Increasing NaCl up to 100 mM caused a significant increase in proline and soluble protein content. The amount of proline at 150 mM NaCl showed no significant change compared to 100 mM NaCl, but the soluble protein sharply decreased at 150 mM NaCl. The enzymatic activities of superoxide dismutase, catalase, and peroxidase significantly increased in response to higher NaCl concentrations. Saturated water deficiency increased significantly, and leaf fresh and dry weights decreased substantially at 100 and 150 mM NaCl. SA enhanced chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content, and leaf fresh and dry weight, depending on the NaCl treatments. SA applications considerably boosted peroxidase and catalase activities despite the presence of NaCl at any concentration. Also, SA significantly improved superoxide dismutase activity at 50 and 100 mM NaCl but could not counter its decrease when the NaCl level was 150 mM. SA significantly reduced saturated water deficiency and proline content despite any of the NaCl treatments. SA mitigated the adverse effects of NaCl on S. mutica by improving antioxidant activity, photosynthetic pigments, and physiological characteristics.
Rahima Khatoon; Md. Mokter Hossain; Limu Akter
Abstract
Sweet gourd (Cucurbita moschata Duch ex Poir) has a high production volume in Bangladesh and holds third rank next to eggplant and radish. Salinity affects almost all growth and physiological aspects of the plant development and eventually reduces yield. Identifying salt tolerance among genetic resources ...
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Sweet gourd (Cucurbita moschata Duch ex Poir) has a high production volume in Bangladesh and holds third rank next to eggplant and radish. Salinity affects almost all growth and physiological aspects of the plant development and eventually reduces yield. Identifying salt tolerance among genetic resources and breeding populations is a valuable study for solving salinity problems. This research aimed to find sweet gourd hybrids tolerant to salinity. Sixteen sweet gourd hybrids (F1) were used for testing salt stress tolerance levels. Salinity stress was induced in pot soil by adding NaCl solutions (4, 8, 12, 16, and control 0.35 dS m-1). The experiment was conducted from October 2019 to March 2020 in a randomized complete block design with three replications. The research was conducted at the Horticulture Research Centre, Bangladesh Agricultural Research Institute (BARI), Gazipur. The measurements included changes in gas exchange parameters against photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (E), quantum yield (Fv/Fm), and relative water content (RWC). Results showed that the gas exchange traits and RWC in all hybrids decreased under stress compared to the control. Photosynthetic parameters in sweet gourd hybrids responded susceptibly to salt stress, thus suppressing overall growth under salinity stress. The reduction of gaseous exchange traits and RWC were minimal in P11 × P12 and P6 × P14. The highest Fv/Fm and RWC occurred in P11 × P12 at 8 dS m-1 salinity stress. The highest Fv/Fm and RWC appeared in P6 × P14 and P11 × P12 hybrids at 12 and 16 dS m-1 salinity stress, so the hybrid P11 × P12 appeared salt tolerant.
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’.
