Mohammad Sayyari; Monirea Moradi Farsa; Ali Azizi
Abstract
The phonological stage in which the abotic stress occurs is effective in determining the content of secondary metabolites in medicinal plants. This research deals with the effects of imposing drought stress at different phenological stages on growth and some physiological and phytochemical responses ...
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The phonological stage in which the abotic stress occurs is effective in determining the content of secondary metabolites in medicinal plants. This research deals with the effects of imposing drought stress at different phenological stages on growth and some physiological and phytochemical responses of Nepeta crispa L as a split plot design in Bu-Ali Sina University during 2019. Drought stress at three levels, including mild, moderate, and severe stress (with 80%, 60%, and 40% of field capacity, respectively) has been applied at two phenological stages (seedling establishment stage with 6 true leaves and pre-flowering stages). Results from statistical analysis show that drought stress has had a significant effect on all evaluated growth traits and phytochemical parameters of the plant including proline content, relative water content (RWC) of leaves, total phenols, flavonoids, tannins, antioxidant activities, and phenolic acids. Imposing drought stress at both phenological stages reduce plant growth, decreasing chlorophyll content and RWC. However, production of phenolic compounds and phenolic acids (including rosmarinic, chlorogenic and caffeic acids) at high level and accumulation of proline through imposing drought stress reduce the adverse effects of stress and increase the medicinal properties of the Nepeta crispa. Also, the effect of drought stress imposing at pre-flowering stage has been greater than its application in the seedling establishment stage. According to the results, it is recommended to impose moderate drought stress at pre-flowering stage to increase biosynthesis of some phytochemical compounds in Nepeta crispa medicinal plants.
Mohammad Sayyari; Maryam Shabanloo; Ali Azizi
Abstract
The effects of hexanal and Pelargonium. essential oil (PEO)-Cucurbita pepo oil (CPO) on the quality and storability of grape cv. Bidaneh Sefid during cold storage was investigated. The treatments included 1) controls as untreated fruuits, 2) Wet controls (treated fruits with solvent (0.02% 0f Ethanol) ...
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The effects of hexanal and Pelargonium. essential oil (PEO)-Cucurbita pepo oil (CPO) on the quality and storability of grape cv. Bidaneh Sefid during cold storage was investigated. The treatments included 1) controls as untreated fruuits, 2) Wet controls (treated fruits with solvent (0.02% 0f Ethanol) that was used in preparation of treatments), 3) hexanal, 4) EFF and 5) combination of PEO and CPO. After treatments, the fruits were stored at 0 ± 1° C and 65-60% RH. At the beginning of the storage, and every 15 days, some parameters were evaluated. The results showed that none of treatments had not significant effect on titratable acidity, pH, total phenol content and fruit quality. The lowest increase in soluble solids (35.59 %) was observed in EFF treatment, which had a significant difference with control untreated fruits. Control fruits with the highest rate of rot (3.5 score) and weight loss (9.3 %) and the lowest firmness (201.3 N mm-2) had less quality than other treated fruits. Hexanal treatment was more successful in maintaining color indices a* and L* in comparison with other treatments. In general, the most effective treatment in preservation postharvest attributes of grape was EFF treatment with significant effects in reducing weight loss, activity of the polyphenol oxidase enzyme, fruits rot and color change of rakis, which seems that good synergistic effects of hexanal treatment, PEO and CPO has maintained quality of grapevine fruits cv. Bidaneh Sefid during 2 months of storage.
Mohammad Sayyari; Sajjad Alvandi
Abstract
In order to preserving of button mushroom during storage, an experiment was carried out through a factorial experiment based on a completely randomized design. In this research the effect of calcium ascorbate (0, 0.4 and 0.8 percent) and hot water treatment (45°C) was investigated on qualitative ...
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In order to preserving of button mushroom during storage, an experiment was carried out through a factorial experiment based on a completely randomized design. In this research the effect of calcium ascorbate (0, 0.4 and 0.8 percent) and hot water treatment (45°C) was investigated on qualitative characteristics such as weight loss, firmness, vitamin C, total phenol, polyphenol oxidase activity (PPO) and color parameters. After treatment, mushrooms were kept at 1 ± 0.5°C and 90% relative humidity and then qualitative characteristics were evaluated after 0, 10, 15, 20 and 25 days. The results showed that calcium ascorbate associated with heat treatment had significant effects on weight loss, firmness, color parameters and PPO activity. The effect of time on all parameters in statistical level 1% and the interaction effect of treatment and time on weight loss, color parameters and PPO activity were significant. The best results in preserving mushroom quality appeared to be obtained from 0.8% calcium ascorbate with heat treatment.
Forough Saydpour; Mohammad Sayyari; Fardin Ghanbari
Abstract
Glycine betaine (GB) is one of the osmotic plant-protecting members that accumulate in response to abiotic stresses. An experiment was, therefore, conducted to test whether GB application at various concentrations (0, 10, 20 and 30 mM) through seed soaking or foliar spray methods would protect cucumber ...
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Glycine betaine (GB) is one of the osmotic plant-protecting members that accumulate in response to abiotic stresses. An experiment was, therefore, conducted to test whether GB application at various concentrations (0, 10, 20 and 30 mM) through seed soaking or foliar spray methods would protect cucumber seedlings, subjected to chilling stress. At two true leave stages, after GB treatment, the seedlings were exposed to chilling six h/day at 3°C for 6 days. Results showed that GB pre-treatment improved growth parameters of seedlings subjected to chilling stress and provided significant protection against chilling stress compared to non-GB-treated seedlings. GB prevented chilling injuries with increasing chlorophyll, proline content and antioxidant activities and decreasing electrolyte leakage, malondialdehyde and hydrogen peroxide content. The highest cold tolerance was obtained with 20 and 30 mM GB application and seed soaking method provided better protection compared to foliar spray method.