Agriculture and horticulture
Z. Ebrahimi; M.R. Morshedloo; M.B. Hassanpour Aghdam
Abstract
To investigate the effects of different salinity levels on the essential oil content, and some morphological and physiological characteristics of two oregano subspecies (Origanum vulgare subsp. gracile (K.Koch) letsw. and O. vulgare subsp. hirtum (Link) letsw.), a factorial greenhouse experiment was ...
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To investigate the effects of different salinity levels on the essential oil content, and some morphological and physiological characteristics of two oregano subspecies (Origanum vulgare subsp. gracile (K.Koch) letsw. and O. vulgare subsp. hirtum (Link) letsw.), a factorial greenhouse experiment was conducted in a completely randomized design with four treatments and three replications. The salinity stress treatment was applied using sodium chloride in Hoagland nutrient solution at four levels of control (no stress), and mild (salinity 30 mM), moderate (salinity 60 mM), and severe (salinity 90 mM) stresses. According to the results, under salinity stress the growth indices, total carotenoids, and chlorophyll index decreased, but the activity of antioxidant enzymes and concentration of malondialdehyde and hydrogen peroxide increased in both subspecies. The wet and dry weight, carotenoids, hydrogen peroxide, and guaiacol peroxidase activity were obtained higher in subsp. hirtum than subsp. gracile. The percentage and essential oil composition were also affected by salinity. With increasing the salinity levels, the essential oil percentage was significantly increased compared to the control and its highest amount (0.8%) was observed under mild stress. Thirty five compounds were identified in both oregano subspecies essential oil. Carvacrol (30-72%: subsp. hirtum crarvacrol more than the other subsp.), γ-terpinene, carvacrol methyl ether, and p-cymene were the main components of both subspecies. The results of this study demonstrated the superiority of subsp. hirtum to the other oregano subspecies in terms of the tolerance to salinity stress and also quantitative and qualitative yields.
A. Mazarie; S.M. Mousavi-nik; A. Ghanbari; L. Fahmideh
Abstract
Water deficit stress is a major environmental limiting factor for plant growth and crop productivity. In present investigation, to study the effects of jasmonic acid on reducing the damage caused by drought on growth parameters, some physiological and antioxidant responses on Salvia officinalis L., a ...
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Water deficit stress is a major environmental limiting factor for plant growth and crop productivity. In present investigation, to study the effects of jasmonic acid on reducing the damage caused by drought on growth parameters, some physiological and antioxidant responses on Salvia officinalis L., a factorial experiment in a completely randomized design with three replications was conducted at the University of Zabol. The experimental treatments included drought stress (irrigated in field capacity, depletion of soil water content up to 50% and 75% of FC condition) and foliar jasmonic acid spray (0, 75 and 150 mg.l-1). The results showed that spraying with a concentration of 150 (mg. l-1) jasmonic acid under drought stress increased the height (% 10.02), fresh and dry weight (27.88% and 12.81%), relative water content (21.04%) and chlorophyll a and b content (12.15% and 10.34%). The highest phenolic content (34.13 mg-1fw), proline concentration (5.52 mg-1fw), essential oil yield (2.1 mg-1fw) and the activities of peroxidase (3.15 mg-1fw) and guaiacol peroxidase (0.76 mg-1fw) were obtained in plants sprayed with 150mg.l-1 jasmonic acidand in depletion of soil water content up to 75% of FC. On the other hand, the highest ascorbate peroxidase (0.76 mg-1fw), superoxide dismutase (5.64 mg-1fw) and catalase (5.12 mg-1fw), were obtained in plants sprayed with 150 mg -1 jasmonic acid under drought stress (depletion of soil water content up to 75 and 50% FC). Based on our results, it seemed that Jasmonic acid, with increasing antioxidant defense and accumulation of osmotic regulators (such as proline), reduced the oxidative stress in plants under drought stress. Moreover, maintaining the relative water content and photosynthetic pigment improved growth conditions of sage plants in drought conditions.
P. Arvin; R. Firouzeh
Abstract
An experiment was conducted to evaluate the effects of plant densities (20, 30, 40, and 50 plants per square meter) and foliar application of gibberellin in two levels (0 and 100 Μg L-1) on some of the physiological and morphological traits of coriander (Coriandrum sativum L.). The experiment, carried ...
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An experiment was conducted to evaluate the effects of plant densities (20, 30, 40, and 50 plants per square meter) and foliar application of gibberellin in two levels (0 and 100 Μg L-1) on some of the physiological and morphological traits of coriander (Coriandrum sativum L.). The experiment, carried out in the research farm of Bojnourd Payame Noor University in 2016, was based on a Randomized Complete Blocks (RCB) with three replications. The effects of 20-plant density with gibberellin spray showed the highest plant dry matter percentage as well as the highest number of lateral branches and leaves. The application of gibberellin increased the sugar content by 12.7% in comparison to the control sample; additionally, the highest sugar content (220.79 mg.g-1 F.W) was obtained in the 20-plant density. By increasing the plant density, the content of chlorophyll a, b, and carotenoids decreased. The interaction effect of the 20-plant density ×gibberellin with 72.11 mg.g-1 F.W caused the highest content of chlorophyll a, while the lowest content was recorded for the 50-plant density ×control with 60.7 mg.g-1F.W. The application of gibberellin caused superiority in both seed yield (686.22 Kg.ha-1) and essential oil (0.327%) compared to the control sample. The highest number of compound umbrella and the highest number of seeds per compound umbrella were obtained in the 20 and 30- plant densities, respectively. However, the 1000-seed weight, ultimate yield, oil yield, and essential oil percentage were the highest in the 50-plant density. In general, in higher densities, the ultimate yield seems to increase due to the increased number of plant per unit area, but the yield components are reduced.
S. Fabriki-Ourang; H.S. Shahabzadeh
Abstract
In this study, the effects of salicylic acid and methyl jasmonate as two inducers were studied on antioxidant activity, photosynthetic pigments and flavonoids under salinity stress in Chelidonium majus L. This experiment was conducted as a factorial in a completely randomized design with four replications ...
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In this study, the effects of salicylic acid and methyl jasmonate as two inducers were studied on antioxidant activity, photosynthetic pigments and flavonoids under salinity stress in Chelidonium majus L. This experiment was conducted as a factorial in a completely randomized design with four replications at Imam Khomeini International University during 2017. The elicitors were treated as foliar and mixed with irrigation. The factors studied included elicitors at three levels (distilled water as control, 2 mM salicylic acid, and 100 µM methyl jasmonate), salinity stress at two levels, urban water as control (EC=0.62 ds/m), salinity at 30 mM NaCl (EC=3.36 ds/m), and plant organs at three levels (leaf, root, stem). The analysis of variance showed that the main effects of salinity, elicitors, organs and their interactions were significant for most of the traits. The results of mean comparison for elicitors showed that methyl jasmonate increased carotenoid, flavonoids and anthocyanin. Both salicylic acid and methyl-jasmonate treatments reduced the amount and activity of catalase, superoxide dismutase and guaiacol peroxidase enzymes under salinity stress. In mean comparison of the triple interaction effects, salinity+salicylic acid+leaf was the best combination of factors for chlorophyll (1.68 mg.g-1 FW) and carotenoid (0.54 mg.g-1 FW) contents. Also, the maximum content for anthocyanin (5.7 OD.gr-1 FW) was observed in non-salinity+methyl jasmonate+leaf and for flavonoids in salinity+non-hormone (3.42 OD.gr-1 FW), non-salinity+salicylic acid (3.27 OD.gr-1 FW) and salinity+methyl jasmonate (3.2 OD.gr-1 FW) in leaf, respectively. The amount of total protein increased in salinity+salicylic acid (56.72 mg.g-1 FW) and salinity+methyl jasmonate (53.27 mg.g-1 FW) in contrast to reduction in salinity+non-hormone (43.35 mg.g-1 FW). In conclusion, by applying the two mentioned elicitors, greater celandine does not need to increase the antioxidant defense system and will potentially improve the yield of biomass and some secondary metabolites under salinity stress.
F. Najafi; S. Mehrabian; R. Khavari-Nejad; Y. Ghorbani
Abstract
In the present study, the effects of different concentrations of NaCl (0, 15, 30, 45, 60, 75 and 100mM) were investigated on some physiological parameters and antibacterial activities of dill (Anethum graveolens L.). Ten-days-old seedlings, prepared in sterilized petri dishes, were transferred into pots ...
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In the present study, the effects of different concentrations of NaCl (0, 15, 30, 45, 60, 75 and 100mM) were investigated on some physiological parameters and antibacterial activities of dill (Anethum graveolens L.). Ten-days-old seedlings, prepared in sterilized petri dishes, were transferred into pots containing washed sand and irrigated with Hoagland nutrient solution. Pots were located in a growth chamber (at 25°C for 16h in light and 18°C for 8h in darkness) and after certain growth period, plants were harvested for analyses. For antibacterial analyses, the plants were treated throughout flowering and fruit production stages. Results showed that in all treated plants, proline content was increased and photosynthetic pigments were decreased in high concentrations of NaCl. Also, the studies on growth factors showed that in dill, these parameters were affected by NaCl. Studies on antibacterial activities showed that in most of the cases, the zone of inhibition was increased by increasing of salt concentration and the antibacterial effect of extract was significant in high concentrations. Of course, choosing the best way and solute for preparing the extract is important for reaching a noticeable antibacterial effect.
T. Heidari; Z. Asrar; F. Nasibi
Abstract
One of the methods employed to enhance plant secondary metabolite production is the use of abiotic elicitors in plants. In this research, the effect of heavy metal nickel as abiotic elicitors was studied on some physiological parameters in Hyoscyamus niger L. to investigate the use of unstressful concentration ...
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One of the methods employed to enhance plant secondary metabolite production is the use of abiotic elicitors in plants. In this research, the effect of heavy metal nickel as abiotic elicitors was studied on some physiological parameters in Hyoscyamus niger L. to investigate the use of unstressful concentration of this metal in order to increase secondary metabolite synthesis in later researches. This research was carried out in the Department of Biology of Shahid Bahonar University of Kerman in a complete randomized design with three treatments and three replicates. The seeds of Hyoscyamus germinated in germinator under gibberellin treatment and then were transfered to the pots of sand and peat. After 40 days of growth, the plants were treated with 50 and 100 µM nickel in hydroponics condition (nickel amounts were added to nutrient solution). According to the obtained results, photosynthetic pigments reduced under Ni treatment while hydrogen peroxide, lipid peroxidation and antioxidant enzymes activity increased. Investigation of Ni stress on main macromolecules such as protein, membrane lipids and chlorophyll showed that the effects of 50 and 100 µM Ni was same, while the PAL activity and polyphenols synthesis were the second responses of plants to stress obserevd in 100 µM concentrations. Therefore, it seems that the higher concentration of Ni (100 µM) was more effective for the increment of secondary metabolite in this plant.
M. Zarooshan; F. Bernard; Z. Heydarian
Abstract
Thymus daenensis Celak. is an endemic plant species in Iran used for medicinal purposes. It seems that In vitro culture is a useful technique for its propagation. In vitro culture conditions cause water stress or hyperhydricity in tissues due to the cut in the plant tissue and changes in levels of plant ...
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Thymus daenensis Celak. is an endemic plant species in Iran used for medicinal purposes. It seems that In vitro culture is a useful technique for its propagation. In vitro culture conditions cause water stress or hyperhydricity in tissues due to the cut in the plant tissue and changes in levels of plant hormones compared to natural conditions and may vary depending on the type of medium, type of agar and available water. Hyperhydricity syndrome is one of the major problems that occur in in vitro growth and through a deformity prevents the propagation of plants. In shoot culture of Thymus daenensis Celak., hyperhydricity happens commonly. In this investigation, the effect of benzyladenine and salicylic acid were studied on shoot hyperhydricity syndrome. For this purpose, disinfected seeds were cultured into glass jars containing Murashige and Skoog (MS) medium with benzyladenine (0.1mgl-1). Non benzyladenine-treated plantlets were transferred to the same medium and benzyladenine-treated plantlets were cultured in four experimental media including without benzyladenine, with 1mgl-1 benzyladenine in presence or without 5µM salicylic acid. Afterward, effects of the mentioned treatments on hyperhydricity, morphological and physiological characteristics of the plant were measured. Results showed that benzyladenine singly caused hyperhydricity in shoot explants of Thymus daenensis. After transferring the explants to the medium free of benzyladenine, hyperhydricity reversed toward normal state and the presence of salicylic acid improved this reversion. Salicylic acid reduced water content in shoot explants and enhanced the amount of photosynthetic pigments. In benzyladenine treated sample, the hyperhydricity was not reversed by salicylic acid.
M. Ghorbanli; N. Adib hashemi; M. Peyvandi
Abstract
In this study, the sodium chloride and ascorbic acid interaction on growth parameters, photosynthetic pigments (chlorophylls a, b and (a+b), carotenoids), amount of soluble sugar and total protein in Nigella sativa L. were investigated in greenhouse condition. This experiment was conducted in randomized ...
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In this study, the sodium chloride and ascorbic acid interaction on growth parameters, photosynthetic pigments (chlorophylls a, b and (a+b), carotenoids), amount of soluble sugar and total protein in Nigella sativa L. were investigated in greenhouse condition. This experiment was conducted in randomized design based on three replications. Plants were exposed to different concentrations of sodium chloride (0, 25, 50, 75 and 100 mM) and ascorbic acid (0 and 10 mM). In plants only exposed to sodium chloride, with the increase of sodium chloride concentration growth parameters, photosynthetic pigments and protein amount decreased compared to control samples while, amount of soluble sugar increased. In plants exposed to sodium chloride and ascorbic acid, growth parameters, photosynthetic pigments, amount of soluble sugars and total protein were higher compared to plants only exposed to sodium chloride. The result showed that spray of ascorbic acid (as an antioxidant) caused resistance against salt stress and decreased side effects of sodium chloride in Nigella sativa L.
