Improvement and breeding
- -; Masomeh Moradi; Mousa Torabi Giglou; Mahsa Ahadzadeh
Abstract
Background and objectives: Basil (Ocimum basilicum L.) is a plant from the Mint family and the genus Ocimum, which has many species, among which O. basilicum is the most useful economic species, and like other plants of the Mint family, it is a source of cyclic compounds and ...
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Background and objectives: Basil (Ocimum basilicum L.) is a plant from the Mint family and the genus Ocimum, which has many species, among which O. basilicum is the most useful economic species, and like other plants of the Mint family, it is a source of cyclic compounds and essential oil. It is also known as a rich source of phenolic compounds (especially rosmarinic acid and caffeic acid) and flavonoids. The plant's vegetative body contains essential oils. Linalool, methyl chavicol, citral, euginol, cineol, geraniol, camphor, and methyl cinnamate are important components of basil essential oil. As the most critical abiotic stress, drought stress plays a crucial role in reducing the yield of medicinal plants. It causes numerous morpho-physiological and biochemical changes in the plant. The performance of the effective substance is influenced by the plant's economic performance and environmental conditions, including drought stress. Stress effects are different at different stages of growth and development.Methodology: To investigate the effect of ascorbic acid on native O.basilicum the native population "Shahre-ray," under drought stress conditions, a factorial experiment in the form of a randomized complete block design was performed in four replications on the research farm of Horticulture Department of Mohaghegh Ardabili University in 2017. Treatments included drought stress (complete irrigation and cessation of irrigation at the beginning of reproductive growth and cessation of irrigation at 50% flowering) and ascorbic acid foliar application at four concentrations of 0.0, 0.5, 1, and 2 mM. This experiment was field operated in May 2016. Before the experiment, the bed preparation operation included plowing, disking, and leveling the ground. The plots of one meter in length and width were created. The seeds were planted in three lines with 15 cm plant spacing. 3-4 cm of rotted manure was used to cover the seeds. After determining the soil texture by the hydrometric method, the mentioned treatments were applied to stress. On the first day, irrigation was a flood, and after germination, irrigation was reduced. All traits were measured in the Physiology Laboratory after the Horticulture Science Department of the Faculty of Agricultural Sciences analyzed the data with SAS software. Also, the treatment averages were compared with Duncan's multi-range test at a probability level of 5%. Results: The results showed that with increasing drought stress intensity, total plant height, stem length, number of leaves, and plant dry weight decreased by 36.08%, 39.75%, 51.26%, and 53.80% compared to the control treatment, respectively. If ascorbic acid spraying could improve these values, the highest root length was obtained under severe stress conditions (beginning of flowering) and treatment with ascorbic acid (15.83 cm), which showed an increase of about 31.91% compared to the control treatment. Drought stress conditions increased proline and essential oil components. Chlorophyll content also decreased under severe stress. Also, by applying drought stress, in all studied traits, the highest amount of ascorbic acid treatment (concentrations of 0.5 and 1 mM) increased, and higher concentrations decreased the content of studied traits. By analyzing the essential oil of plant samples, the main compounds obtained from basil essential oil included geraniol, methyl chavicol, alphapinene, caryophyllene, citral, coupon, carvacrol, neral, linalool, and limonene. In most compounds, essential oil compounds and components were enhanced by increasing drought stress and spraying. The highest amount of essential oil in the stress condition up to the 50% flowering stage and sprayed with 2 mM ascorbic acid was obtained for methyl chavicol compound (33.76%).Conclusion: Applying ascorbic acid increased basil growth under drought stress and created resistance in the plant. Therefore, due to the lack of water resources and the great need of plants for water, it is possible to create resistance to stress in plants by spraying non-toxic and essential elements on them.
Agriculture and horticulture
R. Rostami; B. Esmaielpour; S.A. Hosseini; G. Salimi; A. Etminan
Abstract
To investigate the effects of mycorrhizal fungi on growth characteristics, physiology, and essential oil yield of thyme (Thymus vulgaris L.) under lead (Pb) stress, a factorial experiment was conducted in a completely randomized design with three replications in the research greenhouse of University ...
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To investigate the effects of mycorrhizal fungi on growth characteristics, physiology, and essential oil yield of thyme (Thymus vulgaris L.) under lead (Pb) stress, a factorial experiment was conducted in a completely randomized design with three replications in the research greenhouse of University of Mohaghegh Ardabili (UMA) in 2018. Experimental treatments included different levels of Pb heavy metal (0, 200, and 400 ppm) and inoculation with mycorrhizal fungi (without inoculation, inoculation with Funneliformis mosseae, and Claroideoglomus etunicatum). The results showed that in comparison with the control, with increasing Pb concentration in the soil, plant height (40.56%), number of leaves (36.09%), stem dry weight (43.50%), essential oil percentage (40%), and cell membrane stability (16.14%) were significantly decreased, while proline content (51.72%) and catalase activity (45%) of the leaves increased. Inoculation of thyme with the mycorrhizal fungi was effective in increasing the vegetative indices in presence of Pb heavy metal so that both G. mosseae and G. etunicatum increased the number of leaves by 66.20 and 9.55% compared to the control, respectively. Also, inoculation with G. mosseae under severe Pb stress conditions (400 ppm) increased leaf proline content (11.49%), peroxidase enzyme activity (8.8%), chlorophyll b (21%), total chlorophyll (70.43%), carotenoids (19.6%), and essential oil percentage (55%) compared to the control. Overall, both mycorrhizal fungi were effective on alleviation of Pb toxicity effects and F. mosseae had better performance, especially in terms of morphological traits and essential oil yield. Due to the negative effects of heavy elements on human health, the recommendations to use mycorrhizal fungi to reduce the absorption of heavy metals in plants should be done with more consideration of all aspects including the plant and fungus species type and rate and pollution type.
Agriculture and horticulture
B. Andalibi; M. Mohammadi Azar; B. Esmailpour; F. Shekari
Abstract
This study was conducted to investigate the effects of salicylic acid (SA) and nanosilicon (n-Si) on some morphophysiological characteristics and essential oil of Lallemantia iberica under salinity stress and uncontrolled greenhouse conditions as a factorial experiment based on the randomized complete ...
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This study was conducted to investigate the effects of salicylic acid (SA) and nanosilicon (n-Si) on some morphophysiological characteristics and essential oil of Lallemantia iberica under salinity stress and uncontrolled greenhouse conditions as a factorial experiment based on the randomized complete block design in 2018. The experimental factors included sodium chloride (0, 50, and 100 mM), SA (0, 1, and 2 mM), and n-Si (0, 0.5, and 5 mM). The SA and n-Si treatments were applied at the four-leaf stage (once every seven days) and the salinity treatment was applied at the six-leaf stage of the plant (once every four days) until fully ripening seeds of the plant (yellowing 90% of the leaves and capsules). The results showed that under salinity stress, the plant traits including height, aerial parts dry weight, chlorophyll content, and seed yield decreased and proline and essential oil increased. The application of SA and n-Si improved these traits under salinity stress. The main constituents of L. iberica essential oil included linalool (25%), geraniol (16%), β-cubebene (10.6%), menthyl acetate (9.8%), valencene (3.5%), germacrene-D (2.4%), β-caryophyllene (2.3%), and limonene (1.3%), all of which increased in the salinity treatments compared to the control. The application of SA and n-Si under salinity stress conditions increased limonene, linalool, geraniol, β-cubebene, β-caryophyllene, and valencene and decreased menthyl acetate and germacrene D. In general, the results of this study showed that the application of SA and n-Si could increase the tolerance of L. iberica to salinity stress by creating the osmotic regulation, protecting the content of photosynthetic pigments, and reducing oxidant damage.
Improvement and breeding
B. Esmaielpour; M. Shiekhalipour; M. Torabi-Giglo
Abstract
Soil salinity in arid and semi-arid regions is one of the most important abiotic stresses causing negative effects on the growth and yield of medicinal plants. To investigate the effect of Zn nanoparticles foliar spray at different levels on growth characteristic, antioxidant enzymes, and essential oil ...
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Soil salinity in arid and semi-arid regions is one of the most important abiotic stresses causing negative effects on the growth and yield of medicinal plants. To investigate the effect of Zn nanoparticles foliar spray at different levels on growth characteristic, antioxidant enzymes, and essential oil yield of dragonhead (Dracocephalum moldavica L.) under salinity stress conditions, a factorial experiment was conducted in a completely randomized design with three replications in the greenhouse of Mohaghegh Ardabili University during 2018-2019. Experimental treatments included salinity stress at four levels (0, 50, 100, and 150 mM of NaCl) and foliar spray with Zn nanoparticles at three levels (0, 100, and 500 mg.l-1). Traits including plant height, aerial parts fresh and dry weight, chlorophyll, cell membrane electrolyte leakage, relative water content, proline, antioxidant enzymes, and percentage and yield of essential oil were measured. Results showed that salinity significantly decreased plant height, shoot fresh and dry weight, chlorophyll, the relative water content of leaves, and essential oil yield, and increased electrolyte leakage from cell membranes and proline content of the leaves. While nano-Zn foliar spray reduced the negative effects of salinity stress by increasing the growth and activity of antioxidant enzymes such as ascorbate peroxidase and superoxide dismutase. Treatment of 500 mg.l-1 nano-Zn caused the best-improving effect on traits including plant height, stem dry weight, chlorophyll, electrolyte leakage, antioxidant enzymes, and essential oil yield under salinity stress conditions. Therefore, the use of 500 mg.l-1 nano-Zn is recommended as a reduction of the negative effects of salinity stress in dragonhead.
A. Rahbary; H. Fatemi; B. Esmailpour
Abstract
Recently, various methods have been used to alleviate the detrimental effects of pollutants. The application of biofertilizers with respect to their positive impacts on soil characteristics and environment can be served as a suitable alternative to many of these methods. In order to investigate the two-way ...
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Recently, various methods have been used to alleviate the detrimental effects of pollutants. The application of biofertilizers with respect to their positive impacts on soil characteristics and environment can be served as a suitable alternative to many of these methods. In order to investigate the two-way effect of bacterium Pseudomonas fluorescens on plant growth, physiological and biochemical characteristics of dill (Anethum graveolens L.) under Pb stress conditions, a factorial experiment based on a completely randomized design with three replications was conducted at Mohaghegh Ardabili University. Experimental treatments included Pb stress at two levels (0 and 600 ppm) and bacterial inoculation at three levels (inoculation with Pseudomonas fluorescens strains150 and 159 separately and without inoculation (control)). The results of this study showed that the growth characteristics such as leaf number, plant height, and shoot fresh and dry weight were significantly affected by Pb contamination and shoot fresh and dry weight, leaf number and plant height decreased by 22, 31, 19 and 9%, respectively. The content of proline and carbohydrates in dill showed a significant increase under the influence of lead. Bacterial inoculation also increased the content of proline and plant carbohydrates, which was more pronounced in inoculation with strain150. The activity of antioxidant enzymes was significantly influenced by Pb contamination and bacterial inoculation. Pb increased peroxidase but decreased catalase activity, but inoculation with Pseudomonas bacteria, especially strain 150, significantly increased the activity of both enzymes. In addition, the bacteria were able to reduce the amount of Pb in dill. In general, the results of this experiment indicated that Pseudomonas bacterial inoculation was effective in alleviating the effects of Pb stress on dill via growth promotion and improving enzymatic activity.
B. Esmaielpour; H. Fatemi; M. Moradi
Abstract
Drought stress, as one of the most important abiotic stresses, plays an important role in decreasing the yield of medicinal plants. In order to investigate the effect of nitric oxide on morphophysiological and biochemical characteristics of basil (Ocimum basilicum L.), the native population "Shahre-ray", ...
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Drought stress, as one of the most important abiotic stresses, plays an important role in decreasing the yield of medicinal plants. In order to investigate the effect of nitric oxide on morphophysiological and biochemical characteristics of basil (Ocimum basilicum L.), the native population "Shahre-ray", a factorial experiment was conducted in a completely randomized design under drought stress conditions with three replications in the research greenhouse of Mohaghegh Ardabili University in 2017. Experimental factors included drought stress at three levels of complete irrigation (drip irrigation at three-day intervals throughout the growing season) and complete stop of irrigation at early flowering stage (60 days after planting at 10-12 leaf stage) and 50% flowering (75 days after planting at 14-15 leaf stage) and nitric oxide spray with sodium nitroprusside at four concentration levels of zero (leaf spray with distilled water), 0.5, 1, and 2 mM. The foliar application was carried out from the eight-leaf stage of the plant, with intervals of two weeks to four times. Results showed that stopping irrigation at both mentioned growth stages significantly reduced plant height, plant dry weight, chlorophylls a and b, total chlorophyll, carotenoid, and relative water content, and significantly increased electrolyte leakage rate, leaf proline content, and essential oil percentage. Foliar application of 2 mM nitric oxide significantly increased plant growth under irrigation interruption, especially at 50% flowering. Increasing the concentration of nitric oxide produced the highest essential oil percentage (1.4%) at the early flowering stage under irrigation interruption conditions and significantly increased the content of essential oil components including methyl chavicol, linalool, geranial, geraniol, α-pinene, β-pinene, and myrcene. In general, the results showed that foliar application of nitric oxide at 50% flowering stage under irrigation interruption improved the growth of basil and increased the percentage and components of essential oil via osmotic adjustment, preventing chlorophyll degradation and maintenance of leaf water content.
H. Fatemi; B. Esmaielpour; A.A Soltani-Toolarood; A. Nematolah Zadeh
Abstract
Silicon (Si) is the second most abundant element in the earth crust. Silicon has been shown to ameliorate the adverse effects of heavy metals on plants. This research was aimed to investigate the effects of silicon nano-fertilizer nutrition on growth and physiological characteristics of coriander (Coriandrum ...
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Silicon (Si) is the second most abundant element in the earth crust. Silicon has been shown to ameliorate the adverse effects of heavy metals on plants. This research was aimed to investigate the effects of silicon nano-fertilizer nutrition on growth and physiological characteristics of coriander (Coriandrum sativum L.) under lead stress. The study was conducted in a factorial experiment based on a completely randomized design with four replications in the research greenhouse of Mohaghegh Ardabili University during 2016. Experimental treatments included soil contamination by PbCl2 (0, 500, 1000 and 1500 mg/kg soil) and foliar spraying with silicon nano-fertilizer (0, 1.5 and 3 mM). Morphological studied traits including plant height, leaf number and area, fresh and dry weight of root and plant, root and stem diameter, physiological parameters such as photosynthetic pigments, electrolyte leakage, relative water contents, proline, carbohydrates, phenol, antioxidants were measured. Results indicated that lead stress reduced the morphological characteristics such as plant height, plant fresh and dry weight, and stem and root diameter, so that the increased content of lead led to decrease of plant dry weight, root weight, root and stem diameter, root length, plant height, leaf area and dry weight up to 57, 50, 20, 41, 15, 42 and 25%, respectively. Foliar spraying with silicon (3mM) led to improve most of morphological traits of coriander. The content of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and carbohydrate in leaves was increased with increasing lead concentration in soil. However, silicon foliar spraying improved these traits under lead stress. Proline, phenol, flavonoid and antioxidant capacity were significantly increased with increasing concentration of lead up to 1500mg/kg. In general, it can be concluded that the use of silicon nanoparticles for coriander can reduce the negative effects of lead stress to a satisfactory level.
H. Hadizadeh; M. Mohebodini; B. Esmaeilpoor
Abstract
Roots are the site for biosynthesis or accumulation of major plant secondary metabolites. In recent decades, many researchers have focused on the biosynthesis of valuable secondary metabolites in hairy roots. This study was conducted to optimize the induction andthe culture conditions of adventitious ...
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Roots are the site for biosynthesis or accumulation of major plant secondary metabolites. In recent decades, many researchers have focused on the biosynthesis of valuable secondary metabolites in hairy roots. This study was conducted to optimize the induction andthe culture conditions of adventitious and hairy roots of chicory (Cichorium intybus L.) using auxins IAA, IBA and NAA. This study was performed in two steps. In the first step, the leaf explant was cultured on MS solid medium for rootinduction with different concentrations of IAA and NAA (0, 0.3, 0.6 and 1 mg 1-1). The highest rootinduction (100 %) and the highest mean number of roots were obtained at concentration of 1 mg 1-1 NAA. In the second step, the adventitious and hairy rootsobtained from leaf explants were cultured in MS liquid medium with different concentrations of IAA, IBA and NAA (0, 0.5, 1 and 1.5 mg 1-1). According to the results, the highest fresh and dry weight was obtained in MS liquid medium containing 0.3 mg 1-1 NAA and 1.5 mg 1-1 IBA and hairy roots were only established in treatments containing NAA hormone.
A. Faraji; B. Esmailpoor; F. Sefidkon; B. Abaszadeh; K. Khavazy
Abstract
In order to investigate the effect of salicylic acid and putrescine as foliar spray on plant yield and growth, essential oil yield and composition of summer Savory (Satureja hortensis L.), a field experiment was carried out based on randomized complete blocks design (RCBD), with three replication. ...
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In order to investigate the effect of salicylic acid and putrescine as foliar spray on plant yield and growth, essential oil yield and composition of summer Savory (Satureja hortensis L.), a field experiment was carried out based on randomized complete blocks design (RCBD), with three replication. Different concentrations of salicylic acid (0, 1, 2 and 3mM) and putrescine (0, 0.5, 1, 1.5 and 2mM) were applied as foliar spray at early stages of shooting, blooming and floweing. Results showed that foliar application of salicylic acid and putrescine had significant effect (p<0.01) on some vegetative parameters such as dry weight and yield of total aerial shoots, leaves and inflorescences as well as total chlorophyll concentration. All treatments had a significant effect (p<0.01) onessential oil efficiency, percentage, yield and composition of Satureja hortensis. The highest value of total aerial shoots dry weight (45.63g/p), total aerial shoots yield (5070kg/ha), leaf dry weight (6.39g/p), leaf yield (710kg/ha), inflorescence dry weight (15/65g/p), inflorescence yield (1739kg/ha), and total chlorophyll concentration (1.46mg/l) were observed in 3mM salicylic acid. The essential oil efficiency (2.35kg/ha) and essential oil yield (76.76%) reached a maximum range in 1.5mm putrescine. The concentration of thymol (47.76%) as the main volatile component of summer savory, reached the highest value in 2mM salicylic acid while other components, such as α-pinene, limonene and E-B-ocimene, reached the highest value in 50mg/L putrescine.
