Agriculture and horticulture
Vahideh Samadiyan-Sarbangholi; B. Abaszadeh; Fatemeh Sefidkon; Mehrdad Yarnia
Abstract
Bachground and objective: Deficiency or excess of any growth factor leads to morphological, anatomical, physiological, and growth disorders in plants. Drought stress means a lack of water in the plant. This situation occurs when the amount of transpiration exceeds the amount of water absorption. Low ...
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Bachground and objective: Deficiency or excess of any growth factor leads to morphological, anatomical, physiological, and growth disorders in plants. Drought stress means a lack of water in the plant. This situation occurs when the amount of transpiration exceeds the amount of water absorption. Low irrigation (watering less than the optimal water requirement of the plant) is a strategy to save water, but it affects the plant at a particular stage of growth or the entire season. Biofertilizers develop the root system, changing host plant water relations and plant metabolism. They also activate the defense system, improving access to minerals and tolerance to drought in the host plant, making it environmentally friendly and natural. To manage the prevailing water crisis, one should look for solutions such as reducing water consumption and stopping irrigation at all stages of growth. This is without harming the plant's final performance. In addition, due to the importance of medicinal plants and increasing their biomass, biological fertilizers and the adjustment of drought stress effects have a special place. This experiment was carried out to investigate the effectiveness of Satureja bachtiarica Bunge. against dehydration at different stages of growth. It also investigated the consumption of mycorrhizal fungi and growth-stimulating bacteria to manage plant production with high quality and quantity.Methodology: The experiment was carried out in the form of split plots in the form of a randomized complete block design in three replications in the research farm of Islamic Azad University, Tabriz branch, in 2018. The main and sub-factors were included in 4 water stress (I1: without stress, I2: cut irrigation in stem elongation stage, I3: cut irrigation at the budding stage and I4: cut irrigation at 50% flowering stage) and 5 biofertilizer levels (b1: without inoculation, b2: inoculation with Funneliformis mosseae, b3: inoculation with Rhizophagus irregularis, b4: Funneliformis mosseae + Rhizophagus irregularis and b5: Azosprillium+Pseudomonas+Azetobacter), respectively. The harvest was in full flowering stage.Results: The comparison of the average of irrigation interruptions showed that the most number of leaves, stem diameter, canopy extent, root weight, leaf yield, flowering stem yield, and flowering branch yield belonged to the irrigation interruption at the 50% flowering stage. Inoculation with Funneliformis mosseae mycorrhizal fungus achieved the highest leaf yield (912.06 kg/ha), flowering stem yield (1071.25 kg/ha) and flowering branch yield (1983.32 kg/ha) in inoculation with Azosprillium + Pseudomonas + Azotobacter was observed. The highest percentage of essential oil was found in inoculation with Funneliformis mosseae with an average of 1.76%. The maximum average yield of essential oil at 30.50 kg/ha was observed in the inoculation treatment with Azosprillium + Pseudomonas + Azotobacter. The results of the comparison of the average of the interaction effect showed that the maximum height of the plant and the number of inflorescences with an average of 61.72 cm and 30.46 per plant were found in the interaction effect of the treatment of interruption of irrigation at the stemming stage and inoculation of Rhizophagus irregularis + Funneliformis mosseae, which is about 31 and 39 The percentage increased compared to their lowest value. Stopping irrigation in the budding stage ×Funneliformis mosseae had the highest percentage of essential oil with an average of 2.33%. Stopping irrigation in the stemming stage ×Rhizophagus irregularis had the lowest essential oil percentage. The highest leaf yield (1212.83 kg/ha), flowering stem yield (1494.75 kg/ha), flowering branch yield (2707.58 kg/ha) and essential oil yield (44.39 kg/ha) in the interaction effect of cutting × Azosprillium + Pseudomonas + Azotobacter irrigation was observed at the 50% flowering stage, which increased by 70, 82, 81 and 87% compared to the lowest ones.Conclusion: The correct management of soil fertility, improvement, and maintenance of soil fertility in modern agricultural systems will provide the nutrients needed by the plant and thus enhance the yield. Therefore, in recent years, many studies have been conducted on biological fertilizers. Mycorrhizal fungi are essential factors in the stable plant-soil system, which coexists with more than 85% of plants. Drought stress is one of the most influential environmental factors in plant growth and causes morphological, physiological, and metabolic changes. In addition, biofertilizers increase plant access to nutrients and produce and direct hormones involved in the growth of the root environment. They also increase stress tolerance and enhance yield. Considering the arid and semi-arid conditions of the country and the increase in demand for medicinal plants and Satureja bachtiarica spices, it is recommended to stop irrigation at the 50% flowering stage and use Azotobacter, Azospirillium, and Pseudomonas biofertilizers to obtain the maximum yield of leaves, flowering branches, and essential oil.
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.
Improvement and breeding
M. Edalateyan Kharazi; A. Asgharzadeh
Abstract
To investigate the effects of drought stress, salicylic acid, and polyamines on plant growth yield and oil and seeds essential oil content in Nigella sativa L., a factorial experiment was conducted in a completely randomized design with three replications in the research greenhouse of Shirvan Azad University ...
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To investigate the effects of drought stress, salicylic acid, and polyamines on plant growth yield and oil and seeds essential oil content in Nigella sativa L., a factorial experiment was conducted in a completely randomized design with three replications in the research greenhouse of Shirvan Azad University in 2020-21 cropping year. The experimental treatments included drought stress at four levels (25, 50, 75, and 100% of field capacity) as the first factor and foliar application of salicylic acid, putrescine, and spermidine each at two levels (0.5 and 1 mM) as the second factor. The results showed that the highest number of fertile capsules per plant (12.66), number of seeds per capsule (96.24), and harvest index (58.69%) were obtained in the 100% of field capacity treatment. Also, the highest seed yield per pot was obtained in the 100% of field capacity treatment (16.05 g) and 1 mM salicylic acid (11.46 g). On the other hand, the highest plant height (62.5 cm), dry weight of single plant (6.44 g), biomass in pot (32.2 g), oil content (31.21%), and oil yield (5.71 g.pot-1) were obtained in the treatment of 100% of field capacity + 1 mM salicylic acid and also, the highest essential oil content (0.09%) was obtained in the treatment of 25% of field capacity + 1 mM salicylic acid. Overall, the results showed that full irrigation (100% of field capacity) + 1 mM salicylic acid foliar application was the best treatment for N. sativa under greenhouse conditions. In general, the plant growth characteristics decreased with increasing stress severity, but the negative effects of drought stress were moderated with increasing the salicylic acid foliar application.
Agriculture and horticulture
F. Darabi; N. Abbasi; M.J. Zarea
Abstract
To investigate the role of putrescine and 24-epibrassinolide on the morphophysiological changes of Ocimum basilicum L. in the water deficiency tolerance, an experiment was conducted as a factorial split plot in a randomized complete block design with three replications in the research farm of Agriculture ...
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To investigate the role of putrescine and 24-epibrassinolide on the morphophysiological changes of Ocimum basilicum L. in the water deficiency tolerance, an experiment was conducted as a factorial split plot in a randomized complete block design with three replications in the research farm of Agriculture Faculty, Ilam University during 2017-19 crop years. The experimental treatments included the drought stress at three levels (40, 80, and 120 mm evaporation from Class A evaporation pan) in the main plots and putrescine foliar application at three levels (Put0: 0, Put1: 0.5, and Put2: 2 mM) and 24-epibrassinolide foliar application at three levels (Br0: 0, Br1: 0.5, and Br2: 2 μM) factorially in the subplots. The results showed that the multiple interaction of year, drought stress, putrescine, and 24-epibrassinolide had a significant effect on the traits including chlorophyll a, chlorophyll b, and basil essential oil percentage, so that the foliar application of 2 mM putrescine and 2 μM 24-epibrassinolide at all levels of drought stress, especially 80 mm evaporation from the evaporation pan, caused a further increase in these traits in both years of the experiment, which was higher in the first year than the second one. The optimal irrigation treatment (40 mm evaporation from evaporation pan) with application of 2 mM putrescine and 0.5 μM 24-epibrassinolide and drought stress treatments (80 and 120 mm evaporation from evaporation pan) with application of 2 mM putrescine and 2 μM 24-epibrassinolide had more leaves and secondary branches. The results of this study showed that the drought stress had an important role in reducing the basic factors in basil growth. In general, according to the results obtained, the foliar application of 2 mM putrescine with 2 μM 24-epibrassinolide to improve the physiological activities and increase the essential oil content, and 2 mM putrescine with 0.5 μM 24-epibrassinolide to increase the seed yield could be recommended in basil under drought stress conditions.
Agriculture and horticulture
M. Amani Machiani; A. Javanmard; A. Ostadi; M.R. Morshedloo; J. Chabokpour
Abstract
To evaluate the effects of mycorrhizal fungus Funneliformis mosseae application and harvest time on the quantity and quality of thyme (Thymus vulgaris L.) essential oil in the different irrigation regimes, a field experiment was carried out as a split-split plot in a randomized complete blocks design ...
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To evaluate the effects of mycorrhizal fungus Funneliformis mosseae application and harvest time on the quantity and quality of thyme (Thymus vulgaris L.) essential oil in the different irrigation regimes, a field experiment was carried out as a split-split plot in a randomized complete blocks design (RCBD) with 12 treatments and three replications at the Agriculture Faculty, University of Maragheh, Iran, in 2019. The factors and their levels included 1- the main factor: irrigation regime at three levels of irrigation after 20% (W20 as control), 50% (W50 as moderate stress), and 80% (W80 as severe stress) of maximum allowable depletion, 2- the subfactor: application and non-application of mycorrhiza, and 3- sub-sub factor: harvest time at two levels of June harvest (first harvest) and September harvest (second harvest). The results demonstrated that the highest amounts of plant height, canopy diameter, and dry matter yield of thyme were obtained in the W20 (control)+ application of mycorrhiza fungus+ first harvest treatment. In addition, the highest essential oil content was recorded in W50 followed by W80, which were 38.2 and 23.7% higher than W20 (control), respectively. Also, the application of mycorrhiza fungus increased the essential oil of thyme by 8.5% compared to the non-application of fungus. The highest and lowest content of thymol, γ-terpinene, and p < /em>-cymene were obtained in W50 and W20, respectively. Also, the application of mycorrhiza fungus increased the amount of mentioned compounds, respectively by 3.8%, 3.9%, and 7.1% compared to the non-application of fungus. Overall, it can be concluded that W50 (moderate stress) along with the application of mycorrhizal fungus F. mosseae improved the essential oil quality and quantity of thyme.
Improvement and breeding
M. Beiranvandi; N. Akbari; A. Ahmadi; H. Mumivand; F. Nazarian
Abstract
To study the effect of biochar and superabsorbent on the chemical composition of Satureja rechingeri Jamzad essential oil, under drought stress conditions, a factorial split-plot experiment was conducted in a randomized complete block design with three replications in 2018-2019 at the Medicinal Plant ...
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To study the effect of biochar and superabsorbent on the chemical composition of Satureja rechingeri Jamzad essential oil, under drought stress conditions, a factorial split-plot experiment was conducted in a randomized complete block design with three replications in 2018-2019 at the Medicinal Plant Research Farm of Lorestan University. Treatments included drought stress as the main plot at three levels (100, 80, and 60% of water requirement) and cow manure biochar at two levels (0 and 10 ton ha-1), and stockosorb hydrogel at three levels (0, 60, and 120 mg plant-1) as subplots. Twenty-four compounds were identified in aerial parts essential oil of the plant using GC-MS. The main constituents included carvacrol (76.6%), γ-terpinene (5.8%), p < /em>-cymene (3%), terpinen-4-ol (2.5%), 1,8-cineole (2%), and linalool (0.9%). The results showed that the highest amount of carvacrol (90.8%) was observed in severe moisture stress+biochar+60 mg stockosorb and the lowest (73.8%) was observed in stress-free control treatment with biochar+120 mg stockosorb. The results showed that interactions between drought stress and biochar had a significant effect on essential oil yield. Also, no correlation was observed between the presence and absence of stockosorb superabsorbent with different compounds of Satureja rechingeri essential oil.
A. Abdollahi Arpanahi; M. Feizian; Gh. Mehdipourian
Abstract
To investigate the effects of plant growth promoting rhizobacteria (PGPR) and drought stress on essential oil of Thymus daenensis Clack, a greenhouse experiment was conducted in Shahrekord, Iran in 2017. The experiment was arranged as a factorial in a completely randomized design with three replications. ...
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To investigate the effects of plant growth promoting rhizobacteria (PGPR) and drought stress on essential oil of Thymus daenensis Clack, a greenhouse experiment was conducted in Shahrekord, Iran in 2017. The experiment was arranged as a factorial in a completely randomized design with three replications. The first factor included four levels of irrigation: well-watered (No stress), irrigation after depletion of 20-25% of field capacity (FC) (Low stress), irrigation after depletion of 35-40% of FC (Mild stress) and irrigation after depletion of 55-60% of FC (Severe stress). The second factor included two levels of PGPR treatments: no inoculation (Control) and inoculation with PGPR. The results showed that the morphological parameters were significantly increased in PGPR treatments, while water stress decreased all parameters. The essential oil amount increased in low stress and decreased in severe stress. PGPR inoculation increased the amount of essential oil, although this increase was not statistically significant. PGPR incubation and drought stress had a significant effect on 13 and 14 components, respectively. The interaction of PGPR and drought stress had a significant effect on the oil components. Thymol and carvacrol, two important components of T. daenensis essential oil, decreased with increasing severity of drought stress, but PGPR inoculation increased them, especially at drought stress treatments.
M. Zeynali; B. Maleki Zanjani; P. Moradi; F. Shekari; S.M. Niazkhani
Abstract
Biological stresses such as drought affect the production of secondary metabolites, especially plant sterols (phytosterols). Among the phytoestrols found in pumpkin seeds, betasitosterol is one of the most important components which also have many medicinal properties. In this study, the effect of five ...
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Biological stresses such as drought affect the production of secondary metabolites, especially plant sterols (phytosterols). Among the phytoestrols found in pumpkin seeds, betasitosterol is one of the most important components which also have many medicinal properties. In this study, the effect of five levels of drought stress on seed oil production and its phytosterols was studied in three genotypes and Styriaca variety of pumpkin (Cucurbita pepo L.). Analysis of phytosterols using GC/MS showed that increasing drought stress had a negative effect on oil production from pumpkin ripe seeds, but oil phytosterols, especially betasitosterol, increased and this increase was higher in Styriaca than other genotypes. To confirm these results, the seeds were harvested 15-30 days after flowering and the expression of SQS, PP2A, SMT2, ERG26 and Cycloartenol synthase genes involved in the phytosterol biosynthesis pathway was investigated. The results indicated that, among the different levels of drought stress and genes studied, highest expression level was observed at the rainfed level and at that time, betasitosterol and stigmasterol pathway had the main activity in steroid biosynthesis pathway in pumpkin.
M. Oveysi Omran; M. Zavareh; F. Sefidkon; B. Abaszadeh; S. Asadi-Sanam
Abstract
The aim of this study was to investigate the effects of soil application of potassium fertilizer and foliar application of brasinosteroid on morphophysiological characteristics and essential oil yield of medicinal plant purple coneflower (Echinacea purpurea (L.) Moench) in response to water availability. ...
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The aim of this study was to investigate the effects of soil application of potassium fertilizer and foliar application of brasinosteroid on morphophysiological characteristics and essential oil yield of medicinal plant purple coneflower (Echinacea purpurea (L.) Moench) in response to water availability. Treatments consisted of three levels of water availability (irrigation at 90% (control), 60%, and 30% of field capacity (FC)) in main plots and four amounts of potassium fertilizer (no potassium application (control), 50, 100, and 150 kg K2O ha-1) as well as the foliar application of three brassinosteroid concentrations (distilled water (control), 0.1, and 1 μM) in subplots. Results showed that the highest mean plant height (67.8 cm), number of leaves plant-1(151), number of flowers plant-1 (18.1), flower dry weight (151.9 g plant-1) and aerial parts dry weight (508.6 g plant-1) were obtained in the second year of the experiment under 150 kg ha-1 potassium and normal irrigation treatments. The highest percentage of essential oil (76) was obtained under irrigation at 60% of FC, 150 kg ha-1 potassium, and 1 µM brassinosteroid treatments. In the second year, the maximum amount of essential oil plant-1 (0.67 g) was related to 150 kg ha-1 potassium and 1 μm brassinosteroid treatments. In general, the results of this study showed that irrigation at 60% of FC together with 150 kg ha-1 potassium and 1 μM of brassinosteroid could reduce the effects of drought stress, increase the amount of essential oil plant-1 and improve some morphophysiological characteristics in purple coneflower.
F. Ghasemi; Gh. Mohammadinejad; A. Baghizadeh; H.R. Kavossi
Abstract
In order to improve complex traits such as yield, one of the most effective approaches to select the desired genotypes is the use of selection indices. In this research, in order to evaluate the efficiency of different selection methods under stress conditions, 49 top cumin (Cuminum cyminum L.) genotypes, ...
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In order to improve complex traits such as yield, one of the most effective approaches to select the desired genotypes is the use of selection indices. In this research, in order to evaluate the efficiency of different selection methods under stress conditions, 49 top cumin (Cuminum cyminum L.) genotypes, selected in the second year of a two-year plan were evaluated. This research was conducted as a field experiment in a randomized complete block design with two replications under drought stress conditions in 2012 at the research farm of Shahid Bahonar University of Kerman. The selection indices Smith-Hazel 1 and 2 and Pesek-Baker were computed based on seven traits including plant height, number of lateral branches, umbels, umbellules, seeds, seeds weight and aerial parts weight (traits/plant). Also, the direct and correlated responses of these traits with seed yield were obtained. All three indices were evaluated in two forms, along with yield and without yield. The results of direct and correlated response of traits showed that genotypes with higher number of seeds and umbelluleshad higher yield potential. In the Smith-Hazel 1 and 2 indices, two traits including the number of seeds and umbelluleshad the highest response to the selection, while in the Pesek-Baker index, the number of branches was the highest response to the selection. The results indicated that the Smith-Hazel index had the highest selection efficiency and could be used to select appropriate genotypes in the cumin breeding programs under drought stress conditions.
E. Tohidi Nejad; F. Rastegari
Abstract
In order to evaluate the effects of water stress and fertilizer on yield and quality of chamomile (Marticaia chamomilla L.), a field experiment was conducted based on split plots design with three replications in the research farm of Jiroft Jahad-e Agriculture Organization, in 2010. The experimental ...
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In order to evaluate the effects of water stress and fertilizer on yield and quality of chamomile (Marticaia chamomilla L.), a field experiment was conducted based on split plots design with three replications in the research farm of Jiroft Jahad-e Agriculture Organization, in 2010. The experimental treatments included water stress as main plot in three levels: 40, 80 and 120 mm evaporation from the class A evaporation pan, and fertilizer as sub plot in five levels: control, nitroxyn, bio-phosphate, biosulfore, and cow fertilizer. The traits measured included the number of main stem, number of lateral branches, plant height, number of capitol per plant, capitol diameter, plant dry matter, flower fresh and dry weight, essential oil content, and chamazulene yield. The results showed that the effects of drought stress on all qualitative and quantitative traits were significant (P≤0.01). Means comparison showed that the yield was reduced by 25.1 % in irrigation after 120 mm evaporation, compared to the control. The highest yield and yield componentswas obtained from irrigation after 40 mm evaporation with application of cow fertilizer. The highest values of essential oil percentage (0.85%) and essential oil yield (6.32 kg ha-1) were observed in the treatment of moderate stress and biosulfore. In addition, the highest chamazulene percentage (6.45%) and chamazulene yield (396.8 kg ha-1) were obtained from the nitroxyn and biosulfore fertilizer treatments in the moderate stress condition. Generally, the results showed that cow fertilizer in the severe stress and biosulfore in mild stress conditions were the best treatments in chamomile production.
F. Helali Soltanahmadi; M.R. Amerian; M. Ghiyasi; H. Abasdokht
Abstract
The use of organic materials and nano-fertilizers to control the release of nutrients could be an effective step towards achieving sustainable agriculture. Drought stress is the most important factor limiting the growth and yield of medicinal plants including marigold (Calendula officinalis L.). This ...
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The use of organic materials and nano-fertilizers to control the release of nutrients could be an effective step towards achieving sustainable agriculture. Drought stress is the most important factor limiting the growth and yield of medicinal plants including marigold (Calendula officinalis L.). This experiment was conducted under field conditions in a factorial arrangement in a randomized complete block design with three replications (replication in place) in the Research Farm of the Urmia and Salmas Agricultural Research Center. The first factor was irrigation method at two levels including normal irrigation and irrigation cut in the beginning of flowering, and the second factor was priming treatments in seven levels including the seeds primed with nano fertilizers (iron oxide, zinc oxide and oxide with concentrations of two in thousands) and the seeds primed with organic material (humic acid, 72 mg/L, salicylic acid 2000 micromole and ascorbic acid 200ppm) and control. The results indicated that the priming of seeds with nano materials and priming with organic materials caused an increased plant height, number of capitol, fresh and dry weight of the plant, fresh and dry weight of root, grain yield, harvest index, essential oil percentage, and mineral phosphorus percentage as well as increased quantitative and qualitative yield of marigold, especially in drought stress conditions. Therefore, its application could be recommended for sustainable and organic agriculture.
A. Mohammadi; M. Amini Dehaghi; M.H. Fotokian
Abstract
In order to study the application of humic acid and different irrigation regimes on quantitative and qualitative characteristics of three accession of cumin (Cuminum cyminum L.), an experiment was conducted at the Research Farm of Medicinal Plants, Faculty of Agriculture, Shahed University in 2016. This ...
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In order to study the application of humic acid and different irrigation regimes on quantitative and qualitative characteristics of three accession of cumin (Cuminum cyminum L.), an experiment was conducted at the Research Farm of Medicinal Plants, Faculty of Agriculture, Shahed University in 2016. This experiment was a factorial split plot based on randomized complete block design with three replications. Experimental factors included three irrigation regimes (full irrigation, irrigation after flowering stage and irrigation after grain filling stage), foliar application of humic acid with two levels (0 and 200 mg/lit) and three cumin accessions (Esfahan, Kashan and Sabzevar). The results of analysis of variance showed that the interaction effect of irrigation regime*humic acid*accession had significant effect on single plant dry weight, grain yield, harvest index, chlorophyll a and total. The results showed that the highest single plant dry weight and grain yield were obtained in complete irrigation and humic acid application. Kashan accession had the highest branch number per plant, dry weight per plant, number of seeds per umbrella, grain yield and biological yield. The highest percentage of essential oil yield was observed in Sabzevar accession. The highest grain yield (533.3 kg/ha) was obtained in complete irrigation with the use of humic acid in Kashan accession. The highest average dry matter yield (230 kg/ha) was obtained in complete irrigation with the use of humic acid for Sabzevar accession. The highest amount of chlorophyll a and total was observed in irrigation after flowering stage and lack of application of humic acid in Sabzevar accession. The application of humic acid was not significant on the traits evaluated. The most efficiency of humic acid was obtained in full irrigation. According to the results of this experiment, it can be stated that full irrigation and application of humic acid can increase the yield of Kashan accession in similar experimental conditions.
A. Afkari
Abstract
In order to investigate the effects of drought stress and nitrogen fertilizer on some physiological and biochemical characteristics of basil (Ocimum basilicum L.), a split-plot experiment was conducted based on randomized complete block design in three replications in the research farm of Islamic Azad ...
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In order to investigate the effects of drought stress and nitrogen fertilizer on some physiological and biochemical characteristics of basil (Ocimum basilicum L.), a split-plot experiment was conducted based on randomized complete block design in three replications in the research farm of Islamic Azad University, ArdabilBranch, 2015. The treatments included drought stress (70, 140 and 210 mm of class A evaporation pan) and nitrogen fertilizer at three levels (0, 50 and 100 kg/hectare) respectively. The results showed that the effect of drought stress treatment was significant on the traits investigated. The interaction of drought stress × nitrogen fertilizer had a significant effect on the traits measured, such as chlorophyll a, total chlorophyll, relative water content, dry matter yield, and essential oil yield. In addition, fertilizer treatment caused a significant increase in the physiological characteristics, dry matter yield, and essential oil yield. According to the results, the maximum content of chlorophyll a (2.65 mg/g fresh weight), total chlorophyll (3.42 mg/g fresh weight), relative water content (72.02 percent), dry matter yield (2261.25 kg/hectare), and essential oil yield (7.13 kg/hectare) were obtained for the control treatment and 100 kg of nitrogen per hectare. The maximum content of carbohydrates (3.40 μg/g glucose per fresh weight) and proline (0.681 µmol/g fresh weight) was related to the severe stress treatment. The content of chlorophyll a, b, total, relative water content, carotenoid, and essential oil percent and yield decreased by increasing the drought stress, while the content of carbohydrate and proline increased. Therefore, irrigation at 70 mm evaporation and 100 kg nitrogen fertilizer per hectare could be recommended as the best treatment to achieve the highest levels of chlorophyll a, chlorophyll total, relative water content, dry matter yield, and essential oil yield of basil.
D. Rasouli; B. Fakheri
Abstract
In order to evaluate the effects of drought stress on quantity and quality of yield, physiological characteristics, and essential oil of Ocimum basilicum L. and Ocimum americanum L., a factorial experiment was carried out in a randomized complete block design with three replications in greenhouse condition. ...
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In order to evaluate the effects of drought stress on quantity and quality of yield, physiological characteristics, and essential oil of Ocimum basilicum L. and Ocimum americanum L., a factorial experiment was carried out in a randomized complete block design with three replications in greenhouse condition. Drought stress treatments consisted of control (without drought stress), 80, 60, and 40% of field capacity on two species of Ocimum. The traits measured were fresh and dry weights, essential oil, essential oil performance, carbohydrates, proline, nitrogen, protein, phosphorus and potassium contents. The results indicated that with increasing levels of drought stress from control to 40 percent of field capacity, the content of essential oil, carbohydrates, and proline were increased (28, 46, and 50%) in both species. However, the content of fresh and dry weight, essential performance, nitrogen, protein, phosphorus and potassium were reduced (57, 57.8, 44, 19, 16, 39 and 23%). In O. americanum, the content of fresh and dry weight, carbohydrate, proline, nitrogen, phosphorus, and protein were significantly increased under drought stress; while in O. basilicum, only essential oil content showed higher values significantly. It was observed that the majority of growth factors had the highest performance under low stress (80% of field capacity). Essential oil content, on the other hand, increased significantly under high stress condition, so that in O. basilicum, the highest essential oil content was obtained at 60 percent of field capacity. Our findings indicated that the plant performance and essential oil content were increased under average and moderately severe stress conditions, respectively.
T. Izan; F. Shekari; Y. Nasiri
Abstract
Moldavian balm (Dracocephalum moldavica L.), belonging to the Lamiaceae family, is an annual and aromatic plant, which is used in traditional and modern medicine in the treatment of gastrointestinal and cardiovascular disorders. In order to evaluate the effect of salicylic acid on yield and essential ...
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Moldavian balm (Dracocephalum moldavica L.), belonging to the Lamiaceae family, is an annual and aromatic plant, which is used in traditional and modern medicine in the treatment of gastrointestinal and cardiovascular disorders. In order to evaluate the effect of salicylic acid on yield and essential oil of Moldavian balm under drought stress conditions, a field experiment was conducted as a split plot based on randomized complete blocks design with three replications at the Department of Natural Resources and Watershed of Piranshahr City in 2012. The main factor was irrigation at three levels (40, 80 and 120 mm evaporation from pan), and the sub factor was plant spraying with salicylic acid at three levels (0, 0.5 and 1 mM). Results showed that the effect of drought stress on dry yield, thousand seed weight, harvest index of flowering stem, and essential oil yield was significant. Similar results were obtained for the effect of plant spraying with salicylic acid on dry weight and essential oil yield. It should be noted that dry yield and essential oils yield were most affected by drought stress. In addition, the highest values of thousand seed weight and harvest index of flowering stem was related to the irrigation treatment of 120 mm evaporation. The present study results also showed that the interaction effect of two factors studied on essential oil percentage and essential oil harvest index was significant. In this regard, the maximum amount of essential oil and essential oil harvest index belonged to application of 1 mM salicylic acid in irrigation treatment of 120 mm evaporation from pan.
Gh. Ramezan; B. Abbaszadeh
Abstract
Drought stress is an important environmental factor that reduces the yield of plants. Nepeta pogonosperma Jamzad et Assadi is a perennial plant from Lamiaceae family. Iran is an arid and semiarid region and most of the agricultural lands are faced with drought stress; this is the main reason for reduced ...
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Drought stress is an important environmental factor that reduces the yield of plants. Nepeta pogonosperma Jamzad et Assadi is a perennial plant from Lamiaceae family. Iran is an arid and semiarid region and most of the agricultural lands are faced with drought stress; this is the main reason for reduced yield. In order to investigate the effect of drought stress and planting interval on Nepeta pogonosperma, an experiment was conducted under field conditions in 2012, at Alborz research station, Research Institute of Forests and Rangelands, Karaj, Iran. The experiment was conducted in factorial in the form of a randomized complete block design with three replications. Planting interval factor was in four levels (20×20, 30×30, 40×40 and 50×50 cm), and drought stress factor was in three levels (30, 60 and 90% of field capacity). Analysis of variance showed that the effect of interaction of drought stress × planting interval was significant on diameter of the main stem and the percentage of essential oil at P≤0.05. The effect of planting interval and drought stress was significant on leaf width and length, inflorescence length, yield, essential oil percentage and yield, number of flowering stems and total stems, and number of inflorescences. Mean comparison showed that the maximum leaf width (15.9 mm), leaf length (40.5 mm), and shoot yield (3391 kg/ha) were achieved in the control (90% FC), and the highest number of non-flowering stems (47), number of flowering stems (41), number of total stems (88), number of inflorescences (15), shoot yield (5185 kg/ha), essential oil percentage (3.21%) and essential oil yield (122 kg/ha) were related to 20×20 cm planting interval. The results of this study showed that in order to achieve the maximum shoot yield and essential oil yield, a planting interval of 20×20 cm at a drought level of 60%FC could be recommended.
F. Mohtashami; M. Pouryousef; B. Andalibi; F. Shekari
Abstract
To study the effects of seed priming and foliar application of salicylic acid (SA) on yield and essence of fennel (Foeniculum vulgar Mill.) under drought stress condition, a field experiment was conducted at College of Agriculture, University of Zanjan in the spring of 2012. The experiment was conducted ...
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To study the effects of seed priming and foliar application of salicylic acid (SA) on yield and essence of fennel (Foeniculum vulgar Mill.) under drought stress condition, a field experiment was conducted at College of Agriculture, University of Zanjan in the spring of 2012. The experiment was conducted as a split plot based on complete randomized block design with three replications. In this study, drought stress at reproductive stage with control (full irrigation) was assigned to the main plots and different treatments of seed priming and foliar application with SA including dry seeds (without priming), seeds priming with SA at different concentrations (0, 800 and 1600μmol) and foliar application with SA at different concentrations (800 and 1600μmol) were assigned to the subplots. Results showed that the majority of measured traits including number of umbrella in plant, number of seeds in umbrella, seed thousand weight, harvest index, biomass, grain yield, and essential oil yield significantly decreased under drought stress condition and the essential oil content increased vice versa. Therefore, the highest seed (2925.6kg/ha) and essential oil yield (52.88kg/ha) were obtained in control, and the lowest amount of mentioned traits was obtained in drought stress condition. The results also showed that the effect of seed priming and foliar application of SA on the majority of measured traits was significant. There were no differences about seed yield and essential oil yield between foliar application and priming with SA at a concentration of 1600 μmol; however, the highest seed yield (2579.60kg/ha) and essential oil yield (63.15kg/ha) were obtained in foliar application with SA at a concentration of 1600μmol, and the lowest amounts of mentioned traits were obtained in dry seeds (without priming).
M. Layeghhaghighi; B. Abbaszadeh; S.R. Tabaei Aghdaei; V. Samadiyan Sarbangholi
Abstract
Nepeta, belonging to Lamiaceae family, includes 250 species in the world and 67 species in Iran, 39 of which are native to Iran. In order to investigate the effects of drought stress on yield quantity and quality of Nepeta racemosa Lam., this experiment was conducted in 2011, at the Alborz Research Station, ...
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Nepeta, belonging to Lamiaceae family, includes 250 species in the world and 67 species in Iran, 39 of which are native to Iran. In order to investigate the effects of drought stress on yield quantity and quality of Nepeta racemosa Lam., this experiment was conducted in 2011, at the Alborz Research Station, Karaj, Iran. Drought levels were 100% (control), 80% (low stress), 60% (medium stress), and 40% (severe stress) field capacity (FC). Different traits including plant height, number of tillers, number of lateral branches, root weight, root length, main stem diameter, number of inflourcences, inflorescence length, leaf length, leaf width, yield of leaf, inflorescences, stem and shoot, and essential oil percentage and yield of leaf, inflorescence, stem and shoot were measured at flowering stage. Variance analysis revealed significant effect of drought stress on plant height, root weight, inflorescence length, leaf length, leaf width, yield of leaf, stem, inflorescence, and essential oil percentage of leaf, stem, inflorescence, and essential oil yield of the leaf, stem, inflorescence (P≤0.01), root length, and main stem diameter (P≤0.05). Mean comparison showed that the highest essential oil percentage was observed in leaves (1.72%), shoot (1.27%) and inflorescences (1.93%) at medium stress (60% field capacity). It could be concluded that Nepeta is a drought tolerant plant, and the maximum essential oil percentage could be achieved under medium stress with 60% field capacity.
M. Pouryousef
Abstract
To study the changes of yield and essential oil of fennel (Foeniculum vulgare Mill.) under drought stress condition and different harvesting times, a field experiment was conducted at College of Agriculture, University of Zanjan in the spring of 2011. The experiment was conducted as a split plot based ...
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To study the changes of yield and essential oil of fennel (Foeniculum vulgare Mill.) under drought stress condition and different harvesting times, a field experiment was conducted at College of Agriculture, University of Zanjan in the spring of 2011. The experiment was conducted as a split plot based on complete randomized block design with three replications. In this study, the effects of water stress in three levels including control, drought stress at flowering and grain filling stages were assigned to the main plots and three harvesting times including harvest at soft dough (58% moisture content of grain), hard dough (37% moisture content of grain) and maturity stages (16 % moisture content of grain) were assigned to the sub plots. Results showed that the effect of drought stress on grain and essential oil yield, grain essential oil content, 1000-grain weight, number of umbellet in umbrella, number of grain in umbellet, number of grain in umbrella was significant (p ≤ 0.05). Majority of mentioned traits decreased significantly (p ≤ 0.05) under drought stress condition. Therefore, the highest grain yield (1436.63 kg/ha) and essential oil yield (34.54 kg/ha) were obtained in control treatment (full irrigation) and the lowest amounts of mentioned traits were obtained in drought stress at grain filling stage. According to the obtained results, the effect of harvest time on grain and essential oil yield, grain essential oil content, 1000-grain weight, number of grain in umbellet and number of grain in umbrella, was significant (p≤0.01). Therefore, the highest and lowest grain yield (1425.75 and 784.81 kg/ha) was obtained in hard dough and maturity stages, respectively. In addition, the highest essential oil yield (33.97 kg/ha) was obtained in hard dough stage but there was no significant difference about essential oil yield between hard dough and maturity stages. It can be concluded that the fennel plant is sensitive to drought stress at reproductive growth stages and the quantity and quality of fennel yield can be affected by harvest time.
M. Lotfi; B. Abbaszadeh; M. Mirza
Abstract
In this study the effect of drought stress on morphological traits, metabolites proline accumulation, soluble carbohydrates and the yield of Tarragon (Artemisia dracunculus L.), was evaluated in order to produce Tarragon in drought stress condition as a medicinal plant, and also determine the threshold ...
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In this study the effect of drought stress on morphological traits, metabolites proline accumulation, soluble carbohydrates and the yield of Tarragon (Artemisia dracunculus L.), was evaluated in order to produce Tarragon in drought stress condition as a medicinal plant, and also determine the threshold of stress tolerance. This research was done using randomized complete blocks design with 4 treatments and 3 replications. The stress treatments were included T1 (100% of field capacity), T2 (80% of field capacity), T3 (60% of field capacity) and T4 (40% of field capacity). According to the results of statistical analysis, the drought stress had significant effect on morphological traits, flowering shoot yield, proline and soluble carbohydrates. In addition, the enhancement of drought stress led to decrease in plant height, canopy diameter, leaf length, leaf width and leaf surface, stem diameter, the length of longest lateral shoot, root length and its development, shoot yield and dry leaf yield. Comparison of treatment means showed that the highest plant height, canopy diameter, leaf length, leaf width and leaf surface, stem diameter, the length of longest lateral shoot, root length, shoot yield and dry leaf yield were related to T1 (non stress); in addition, the highest amount of proline, soluble carbohydrates and root development were related to T4 (40%FC). Therefore, drought stress had negative effect on most morphological traits and flowering shoot yield; however, it led to increase in the root length, proline and soluble carbohydrates of flowering shoots.
M.H. RAD; K. Jaimand; M.H. Assareh; M. Soltani
Abstract
Drought stress has different effects on morphological, physiological and biochemical processes of plants. Moreover, the quantity and quality of essential oil are affected by drought stress. Eucalyptus species including Eucalyptus camaldulensis Dehnh. are considered as rich sources of essential oils especially ...
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Drought stress has different effects on morphological, physiological and biochemical processes of plants. Moreover, the quantity and quality of essential oil are affected by drought stress. Eucalyptus species including Eucalyptus camaldulensis Dehnh. are considered as rich sources of essential oils especially 1,8-cineol. In order to study the effect of drought stress on essential oil yield, the type of chemical compounds and also water use efficiency in E. camaldulensis, this research was conducted in a completely randomized design with three treatments including 100, 70, and 40% field capacity and three replications. The experiment was carried out in combat desertification research station of Shahid Sadoughi under lisymetry conditions. Results showed that increasing of soil moisture led to the increased production of essential oil. However, mild drought stress resulted in increased essential oil yield and improved water use efficiency. Mild drought stress compared to other treatments (p < 0.001), improved the production of 1, 8-cineol, however it was observed that it decreased or stopped the production of many other compounds. The percentage of 1, 8 - cineol in the treatments of 100, 70 and 40% field capacity, were, 69.33, 78.13 and 51.87, respectively. The production of α-pinene, as another important compound was also affected by enough moisture (without stress) so that It's value showed significant difference with other treatments (p <0.001). The percentage of α-pinene in the treatments of 100, 70 and 40% field capacity, were, 14.0, 7.03 and 4.06, respectively. The moisture treatments including 100% FC (without stress), 70% FC (mild stress) and 40% FC (severe stress) were studied with three replicates and completely randomize design.
F. Sayadi; A. Rahimi; H. Dashti; A. Tajabadi pour
Abstract
In this study, the effects of drought and nitrogen were analyzed on morphological traits and dry matter allocation of Isabgul (Plantago ovata) at Vali-e-Asr University of Rafsanjan in 2010. The research was conducted using factorial experiment based on RCD design with 3 replications. The factors included ...
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In this study, the effects of drought and nitrogen were analyzed on morphological traits and dry matter allocation of Isabgul (Plantago ovata) at Vali-e-Asr University of Rafsanjan in 2010. The research was conducted using factorial experiment based on RCD design with 3 replications. The factors included nitrogen (0, 60, 120 and 180 mg N.Kg-1 soil) and soil moisture (100, 80, 60, 40 % FC). Results indicated that drought, nitrogen and their interaction significantly affected seed yield and total dry weight. The highest seed yield (1.72 g.plant-1) was obtained at 120 mg N.Kg-1 soil which was 77% higher than that in control. In 80% FC treatment, using 120 mg N.Kg-1 soil caused 93% increase in total dry weight, compared to control. In addition, with increasing drought stress, dry matter partitioning benefited the root and root mass ratio (RMR) increased significantly. However, no significant changes were recorded for shoot mass ratio (SMR) and grain mass ratio (GMR). Also, with increasing nitrogen fertilizer, more dry matter was transferred to the leaves and less dry matter was transferred to the seed.
L. Jafarzadeh; H. Omidi; A. Bostani
Abstract
To investigate the effect of drought stress and bio-fertilizer (nitrogen) on flower yield, yield components, photosynthesis pigments and proline content of Calendula (Calendula officinalis L.), a study was performed at Shahed University Agricultural Research Station, located 30 km south of Tehran. A ...
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To investigate the effect of drought stress and bio-fertilizer (nitrogen) on flower yield, yield components, photosynthesis pigments and proline content of Calendula (Calendula officinalis L.), a study was performed at Shahed University Agricultural Research Station, located 30 km south of Tehran. A split-plot experiment was conducted in randomized complete block design (RCBD) with three replications in cropping years of 2010-2011. Drought, as the main factor, included soil water potential (SWP) of 0.5 atm and equal to field capacity (FC) as control, SWP of 3.5 atm as moderate stress, SWP of 6.5 atm as relatively sever stress, and SWP of 10 atm as severe stress and was applied to the four-leaf stage. Application of bio-fertilizer (nitrogen) as sub factor including control, 2 liters/ha bio fertilizer (nitrogen) with water irrigation and inoculation of 2 liters/ha bio-fertilizer (nitrogen) with seed treatment), were considered in subplots. Results showed that drought, application of bio fertilizer (nitrogen) and its interaction had a significant effect (P≤0.01) on plant height, flower yield, photosynthesis pigment content, proline content, and flower extract percentage. The highest flower yield (574.46 kg.ha-1) and yield of flower extract (22.79 %) were obtained at a soil water potential (SWP) of 0.5atm (FC). Also, the highest plant height (27.11cm) and photosynthesis pigment contents (17.59 mg/g) were obtained under moderate stress (SWP of 3.5atm). Proline content under optimum irrigation (SWP of 0.5atm or FC) was 47 % lower than that of relatively severe stress (SWP of 6.5atm). Based on the results, the highest plant height, flower yield, proline content and yield of flower extract were obtained from inoculation of bio-fertilizer (nitrogen) with seed treatment. In generall, results showed that calendula along with application of two liters/ha bio-fertilizer (nitrogen) with seed inoculation can tolerate relatively severe levels of drought (SWP of 6.5 atm).
H.R Eisvand; A. Sharafi; A. Ismaeili
Abstract
Satureja khuzistanica Jamzad. belongs to the family labiateae of which several species are growing in different regions of Iran. Germination is one of the important growth stages in plant life cycle that usually is affected and disturbed by unfavorable conditions. Drought stress is considered as an important ...
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Satureja khuzistanica Jamzad. belongs to the family labiateae of which several species are growing in different regions of Iran. Germination is one of the important growth stages in plant life cycle that usually is affected and disturbed by unfavorable conditions. Drought stress is considered as an important unfavorable factor for a main part of Iran. Seed priming is a technique to improve seed quality for stress conditions. The study was performed in a factorial experiment based on a completely randomized design with three replications and three factors. The first factor consisted of three levels of moisture stress (0, -4 and -8 bar), the second factor was osmopriming (0, -4 and -8 bar) and the third factor consisted of two levels of priming temperature (15 and 25 °C). PEG6000 was used to induce osmotic stress in priming and germination medium. Germination percentage and rate, seedling fresh and dry weights, seedling length and vigor index decreased by increasing drought stress, while the number of root increased up to -4 bars and then decreased. Hydro and osmopriming could improve the seed quality. Interaction effect of drought and osmotic potential of priming was significant for germination percentage and rate, seedling dry weight, number of root and vigor index. The seeds hydroprimed at 15°C had the highest germination percentage and rate, vigor index, seedling dry weight and number of roots under control (0 bar) and mid stress (-4 bar) conditions, while the highest germination rate and vigor index were recorded for the seeds primed at -4 bar and 15°C under severe drought condition (-8 bar). The longest roots were obtained at osmopriming at -8 bars and 25°C in control and drought conditions. All traits were affected by priming temperature, except the number of root, as most of the traits primed at 15°C showed a better condition.
