Improvement and breeding
B. Asghari; S. Mafakheri; M. M. Zarrabi
Abstract
Background and Objectives: Hibiscus sabdariffa L., commonly known as Roselle, is a plant cultivated in many regions of the world regions. Roselle has been used as a medicinal herb in traditional medicine for controlling and treating different diseases and physical ailments. These therapeutic effects ...
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Background and Objectives: Hibiscus sabdariffa L., commonly known as Roselle, is a plant cultivated in many regions of the world regions. Roselle has been used as a medicinal herb in traditional medicine for controlling and treating different diseases and physical ailments. These therapeutic effects are attributed to active compounds such as carotenoids, fatty acids, and phenolic compounds, including phenolic acids and flavonoids. One common method to stimulate plants for increased production of active compounds is subjecting them to various types of stresses, such as drought or salinity, along with plant growth regulators. This study investigated salicylic acid's effect on the phytochemical content and various biological properties of Roselle plants under water scarcity conditions.Methodology: The experiment was conducted as a factorial experiment in a completely randomized design, including irrigation intervals at three levels: three days (D1), five days (D2), and seven days (D3), and foliar application of salicylic acid at three levels: 0 (SA0), 0.75 mM (SA1), and 1.25 mM (SA2), with three replicates in a research greenhouse at the International Imam Khomeini University. The required seeds for cultivation were obtained from Pakanbazr Company in Isfahan. The imposition of drought stress through irrigation intervals of 3, 5, and 7 days started at the 4-leaf stage of the plants, and the plant spraying with salicylic acid was performed at the 6-leaf stage, three days before the start of irrigation treatments. The measurement of electrolyte leakage and malondialdehyde content was carried out to determine membrane stability and lipid peroxidation level. Additionally, the measurement of proline content and the activity of three antioxidant enzymes, including peroxidase, catalase, and ascorbate peroxidase, was performed in different samples. Furthermore, the total phenolic, flavonoid, and anthocyanin contents, as the main secondary metabolites of Roselle plants, were measured. The biological and medicinal properties, including the free radical scavenging activity (DPPH) and α-glucosidase inhibitory activity, were also evaluated. The obtained data were analyzed using SAS statistical software version 9.4. Mean comparisons were conducted using Duncan's multiple range test at a significance level of 5%.Results: The results showed both electrolyte leakage and malondialdehyde content increased significantly with increasing levels of applied drought stress on Roselle plants. However, overall, applying salicylic acid treatments led to a decrease in both indicators. The measurement of proline content in Roselle samples showed that the highest amount of proline was observed in plants subjected to the highest drought stress and treated with the 1.5 mM salicylic acid solution. The activity of all three antioxidant enzymes increased with the intensity of the applied drought stress and the concentration of salicylic acid solutions. Roselle's highest levels of phenolic and anthocyanin content were observed in samples sprayed with 1.5 mM salicylic acid solution. The change in anthocyanin content of Roselle plants also demonstrated that increasing the severity of water scarcity resulted in higher levels of this compound. The highest DPPH free radical scavenging activity was observed in Roselle samples grown under the highest drought severity and sprayed with the highest concentration of salicylic acid (61.93%). The highest antioxidant activity was also observed in samples treated with the highest concentration of salicylic acid solution in all irrigation regimes. The highest α-glucosidase inhibitory activity (69.2% and 67.7%) was associated with Roselle samples grown under the highest applied drought severity, sprayed with 1.5 mM and 0.75 mM salicylic acid solutions, respectively.Conclusion: It can be concluded that the use of salicylic acid as a growth regulator can contribute to the enhancement of phytochemical content, especially secondary metabolites such as phenolic and flavonoid compounds, anthocyanins, and the elevation of defensive parameters such as the activation of antioxidant enzymes, as well as an increase in osmolyte content like proline in Roselle plants. These effects assist the plants in exhibiting greater resistance to drought stress and mitigating the negative impacts of this type of stress on the plant.
Phytochemistry (extraction, identification and measurement of active components)
S. Mafakheri; R. Hallaj; B. Asghari
Abstract
Dragonhead with the scientific name of Dracocephalum moldavica L., is an annual medicinal and aromatic herbaceous plant from Lamiaceae family. In this research, D. moldavica seed oil, aqueous, and ethanol extracts were prepared and quantity and quality of fatty acids, phytosterols amount, phenolic and ...
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Dragonhead with the scientific name of Dracocephalum moldavica L., is an annual medicinal and aromatic herbaceous plant from Lamiaceae family. In this research, D. moldavica seed oil, aqueous, and ethanol extracts were prepared and quantity and quality of fatty acids, phytosterols amount, phenolic and flavonoid compounds contents, and DPPH radicals scavenging activity were measured. The seed oil was extracted by cold press method. The results showed that the highest amount of palmitic and stearic acids (9.4 and 3.55%, respectively) was obtained in the ethanol extract. While, the highest amount of oleic (9.7%), linoleic (19.53%), and α-linolenic (59.01%) acids were found in the oil. The ethanol extract exhibited the highest amount of total phytosterol (833.86 mg.100 g-1 DW), γ-tocopherol (38.72 mg.100 g-1 DW), and total tocopherol (39.21 mg.100 g-1 DW). The highest total phenolic (17.4 mg GAE.g-1 DW) and flavonoid (112.12 mg QE.g-1 DW) contents were found in the ethanol extract of seeds and lowest of them (near to zero) was found in the seed oil. Also, the ethanol extract showed the highest DPPH radicals scavenging activity. Overall, ethanol is recommended as the best solvent for extracting dragonhead seed extract to maintain more qualitative properties.
Improvement and breeding
J. Gheshlaghpour; R. Khademian; B. Asghari; B. Sedaghati
Abstract
To evaluate the silicon effects on morphological characteristics as well as the percentage and composition of basil (Ocimum basilicum L.) essential oil under cadmium stress, a factorial greenhouse experiment was conducted in a completely randomized design. The treatments included cadmium metal (Cd) as ...
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To evaluate the silicon effects on morphological characteristics as well as the percentage and composition of basil (Ocimum basilicum L.) essential oil under cadmium stress, a factorial greenhouse experiment was conducted in a completely randomized design. The treatments included cadmium metal (Cd) as the first factor at three levels of 0, 25, and 50 mg kg-1 soil and silicon (Si) as the second factor with concentrations of 0, 1, and 2 mM. The characteristics including root length, fresh and dry weight of roots, plant height, fresh and dry weight of stems, stem diameter, number of leaves, fresh weight of leaves, number of buds, number of sub-stems, and percentage and composition of essential oil were evaluated. The results showed that Cd had negative effects on all studied morphological characteristics and significantly decreased their values compared to the control. However, Si treatment improved all these traits and with increasing the concentration of this element, a significant increase in the values of these traits was observed. Application of Si in the concentration of 2 mM caused 63.8, 81, 61, and 61% increase in the number of sub-stems, root fresh weight, stem fresh weight, and number of buds compared to the control, respectively. The amounts of five major constituents of basil essential oil including 1,8-cineole, linalool, estragole, methyl eugenol, and eugenol were affected significantly with the Cd and Si treatments. However, the interaction of these two treatments showed a significant effect only on the three compounds 1,8-cineole, linalool, and methyl eugenol. The maximum amounts of 1,8-cineole (5.06%) and methyl eugenol (6.21%) were observed in the plants which simultaneously exposed to the highest concentrations of Cd and Si. The amount of linalool was also decreased with the presence of Cd and increased with the Si treatment. The Cd treatment increased the amount of estragole by 12.8% and decreased the amount of eugenol by 25.2%. The Si treatment also increased the amount of estragole by 23.9% and decreased the amount of eugenol by 18.3%.
S. Mafakheri; B. Asghari; M. Shaltooki
Abstract
In order to investigate the effects of biological, chemical and nano-fertilizers on qualitative and quantitative factors of Lallemantia iberica (M.B.) Fischer & Meyer, an experiment was conducted under greenhouse conditions in 2016, at the research greenhouse of Imam Khomeini International University, ...
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In order to investigate the effects of biological, chemical and nano-fertilizers on qualitative and quantitative factors of Lallemantia iberica (M.B.) Fischer & Meyer, an experiment was conducted under greenhouse conditions in 2016, at the research greenhouse of Imam Khomeini International University, Qazvin, Iran. The experiment was conducted in a randomized complete block design with 9 treatments and 5 replications. Treatments included control (no fertilizer), biophosphat, nitroxin, nano fertilizer, chemical fertilizer, biophosphat×nitroxin, nitroxin×nano fertilizer, biophosphate×nano fertilizer, and biophosphat×nitroxin×nano fertilizer. Analysis of variance revealed that treatments significantly affected the plant height, fresh and dry weight, essential oil content, and essential oil constituents of dragon’s head. The maximum plant height (35gr) was obtained by applying chemical fertilizer, the highest fresh and dry weight (36.05 gr and 5.09 gr respectively) were found in the treatment with nitroxin×nano fertilizer, and the highest essential oil percentage with an average of 0.57% belonged to the biophosphate×nano fertilizer treatment. Twenty-four compounds were identified in the essential oils of L. iberica, of which the main constituents were limonene, linalool, verbenone, ß-caryophyllene, germacrene-D and β-cubeben. The highest limonene (7%) occurred with the nitroxin×biophosphate; the maximum amount of linalool (17.9%) was obtained by nitroxin×nano fertilizer; maximum percentage of verbenone (8.8%) was found in the treatment with biophosphate×nitroxin×nano fertilizer; the highest percentage of β-caryophyllene (12%) was observed with biophosphate×nano fertilizer; the highest amount of germacrene-D and β-cubeben (15% and 11.5%, respectively) in the essential oil were obtained by application of nano fertilizer. In addition, our results indicated that the combination of nano, nitroxin and biophosphate fertilizers could improve the growth and quality of dragon’s head plants.
