Mojtaba Kaboodkhani; Hadi salek mearaji; Keyvan aghaei; Afshin Tavakoli
Abstract
Quinoa is one of the salinity tolerant plants, capable of playing an important role in providing human food in the future. In order to investigate the effect of salinity stress on physiological traits and yield of quinoa cultivars, a two-factor factorial experiment was conducted as random complete block ...
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Quinoa is one of the salinity tolerant plants, capable of playing an important role in providing human food in the future. In order to investigate the effect of salinity stress on physiological traits and yield of quinoa cultivars, a two-factor factorial experiment was conducted as random complete block design with three replications in 2020 year under greenhouse conditions. Experimental treatments include three quinoa cultivars (Titicaca, Q26, and Giza1) and three salinity levels (0, 15, and30 dS/m). Salinity stress reduced traits such as photosynthetic pigments, relative leaf water content, and grain yield. The chlorophyll a and b content in control conditions, compared to the salinity level of 30 dS/m, have decreased by 46% and 77%, respectively, with the yield dropping by 35.6%, but the decrease in relative water content has been 12.6%. Electrolyte leakage, proline and malondialdehyde content, catalase, and guaiacol peroxidase activity have increased under salinity stress condition. The Q26 cultivar has had the highest content of carotenoids, chlorophyll a, relative water content, soluble proteins, proline, and catalase activity, compared to the others. Titicaca cultivar has had lower malon-dialdehyde (MDA) content and electrolyte leakage than Q26 and Giza1 cultivars, which indicates the least damage to cell membranes, being superior to the other two cultivars. Giza1 cultivar also has had higher chlorophyll b and carotenoids content than the other two cultivars. Q26 and Giza1 cultivars are probably the most resistant and sensitive cultivars to salinity stress, respectively.
Somaye Amraee Tabar; Ahmad Ershadi
Abstract
In this study, the drought tolerance threshold and relationships between some biochemical and physiological responses of two stone fruit rootstocks, Cadaman and GF677, have been investigated. For this purpose, a pot experiment has been carried out in a greenhouse using factorial trial based on a completely ...
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In this study, the drought tolerance threshold and relationships between some biochemical and physiological responses of two stone fruit rootstocks, Cadaman and GF677, have been investigated. For this purpose, a pot experiment has been carried out in a greenhouse using factorial trial based on a completely randomized design with three replications. One-year-old rooted cuttings of two rootstocks are exposed to drought stress (-0.1 (control), -0.6, -1.1, -1.6 MPa) by adding different amounts of polyethylene glycol-6000 to Hoagland nutrient solution. Significant increase in electrolyte leakage and decrease in leaf relative water content of Cadaman and GF677 rootstocks has occurred at -0.6 and -1.1 MPa, respectively. Concentration of photosynthetic pigments and quantum yield of photosystem II (FV/FM) are less affected by drought stress, decreasing significantly in Cadaman and GF677 rootstocks at -1.1 and -1.6 MPa, respectively. Under severe drought stress, photosynthesis, transpiration, intercellular CO2 concentration, and stomatal conductance in Cadaman rootstock decline more considerably, compared to GF677. Moreover, at drought stress of -1.6 MPa, GF677 does not significantly reduce its photosynthesis, despite a substantial decrease in transpiration; however, the relative decrease in photosynthesis of Cadaman at -1.6 MPa has been much greater than the relative decrease in its transpiration and intercellular CO2 concentration, which, in turn, results in a drop in water use efficiency and mesophilic conductance of Cadaman leaves, compared to GF677. It seems that considerable reduction in photosynthesis in Cadaman rootstock, along with stomatal limitations, is largely due to non-stomatal constraints such as loss of cell membrane intact and reduction of chlorophyll, carotenoids and chlorophyll fluorescence. Results show that GF677 rootstock has higher tolerance to severe drought stress, compared to cadaman.
masoud fattahi; Abdorahman Mohammadkhani; Behroz Shiran; Bahram Baninasab; Rodabe Ravash
Abstract
The present experiment has compared the resistance of different mycorrhizal pistachio rootstocks to salinity and drought stress in a completely randomized design with three replications. It has used Funneliformis mosseae and four pistachio species, Badami-e Riz Zarand, Qazvini, Sarakhs, and UCB1. In ...
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The present experiment has compared the resistance of different mycorrhizal pistachio rootstocks to salinity and drought stress in a completely randomized design with three replications. It has used Funneliformis mosseae and four pistachio species, Badami-e Riz Zarand, Qazvini, Sarakhs, and UCB1. In addition, the experiment of water stress in 4 levels (100%, 80%, 60%, and 40% FC), and experiment of salinity stress in 4 levels (0.91, 7.57, 16.12, and 24.63 dSm-1), have been applied for 60 days. At the end of the experiment, different characteristics such as total biomass, leaf area, tissue moisture percentage, and electrolyte leakage have been measured. Also, during the experiment, total chlorophyll, carotenoids and anthocyanin pigments have been surveyed and analyzed. The results indicate that mycorrhizal symbiosis has improved total biomass and leaf moisture content under both drought and salinity stress conditions, wherein tissue moisture content and total leaf chlorophyll content have decreased and anthocyanin content and electrolyte leakage increased. As for the lowest leaf, stem and root moisture content have been observed at the highest drought and salinity levels with UCB1 having the highest biomass and moisture under salinity stress and the highest leaf and stem moisture content and lowest electrolyte leakage are observed in Sarakhs rootstock under drought stress. It seems UCB1 and Sarakhs symbiotic with mycorrhiza can be useful for salinity and drought stress, respectively.
Maryam Tatari; Reza Abbasi alikamar
Abstract
In order to determine the best time and amount of Glycine Betaine (GB) in increasing tomato yield in drought stress condition, an experiment was carried out in Split Plots on RCBD design with four replications, during 2016. The experimental factors included main factor (irrigation period in 6 and 12 ...
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In order to determine the best time and amount of Glycine Betaine (GB) in increasing tomato yield in drought stress condition, an experiment was carried out in Split Plots on RCBD design with four replications, during 2016. The experimental factors included main factor (irrigation period in 6 and 12 days) and sub factors including time (in 3 levels including sowing, flowering and fruit set) and amount (in 3 levels including 0, 3 and 6 kgha-1) of GB application. The results from RWC, leaf area and electrolyte leakage showed the efficiency of GB application in stress condition. Using GB in non-stress condition led to decrease in fruit weight and no significant difference was observed between 3 and 6 kgha-1 dosages. In stress condition, 3 kgha-1 GB application in sowing, flowering and fruit set stage increased fruit weight by 33%, 40% and 60% respectively compare to average fruit weight of control treatments. Although the positives effect of 3 kgha-1 GB at flowering time on fruit yield was obvious (62% higher) in this study, it seems that the application of this amino acid in non-stress conditions had some toxic effects on tomato fruit yield.
Hamideh Igdari; Ebrahim Ganji Mogadam; Ahmad Asgarzadeh
Abstract
Arizona Cypress (Cupressus arizonica L.) and Thuja (Thuja orientalis L.) are very important evergreen and mainly used as ornamental trees. This study was carried out in two independent experiments with the main purpose of evaluating of freezing tolerance of Arizona Cypress and Thuja with eight levels ...
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Arizona Cypress (Cupressus arizonica L.) and Thuja (Thuja orientalis L.) are very important evergreen and mainly used as ornamental trees. This study was carried out in two independent experiments with the main purpose of evaluating of freezing tolerance of Arizona Cypress and Thuja with eight levels of temperatures (control, -10, -15, -20, -25, -30, -35, -40℃) in a completely randomized design. Proline, Electrolyte leakages, Soluble carbohydrate and Re-growth were measured. Result showed that, in both species Proline and Electrolyte leakages increased. Re-growth percentage decreased dramaticaly in both species with lowering temperature level. so that any Re-growth was observed for Thuja and Arizona Cypress in the -30 and -20℃, respectively. Interactions between Soluble carbohydrate and temperature were not significant for Thuja but decreased significantly (P>0.01) in Arizona Cypress. There was a negative significant correlation between Re-growth, in Thuja (-0.895ôô) and Arizona Cypress (-0.646ôô) with temperature. According to the results, Arizona Cypress was more susceptible to freezing compared to Thuja.
Bijan Mehregan; Sadegh Mousavi Fard; Abdolhossein Rezaei Nezhad
Abstract
The present study aimed to investigate the effect of silicon (Si) on alleviation of the drought-reverse effects in two Althernanthera genotypes “Entire leaf” and “Undulated leaf”. Pot experiment, consists of equal parts of soil, sand and manure, was carried out as factorial based ...
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The present study aimed to investigate the effect of silicon (Si) on alleviation of the drought-reverse effects in two Althernanthera genotypes “Entire leaf” and “Undulated leaf”. Pot experiment, consists of equal parts of soil, sand and manure, was carried out as factorial based on a completely randomized design with six replications. After plants establishment, 0, 1 and 2 mM of silicon were weekly sprayed on plants grown under drought stress conditions (90% field capacity (FC), 75 and 55 percent FC). Si treatment started one week before the beginning of drought stress. Samples were taken after 12 weeks of treatment. The analysis of variation showed that increasing drought stress significantly affected all morphological (plant height, stem diameter and root length), physiological (fresh and dry weight of stem and root, relative water content, electrolyte leakage) and biochemical (chlorophyll a, chlorophyll b, total chlorophyll, proline and anthocyanin) characteristics. Whereas, silicon application (especially with 2 mM concentration) alleviated the stress effects and improved growth parameters. Electrolyte leakage as an indicator of cell membrane integrity was decreased by application of silicon. Results of this study showed that different varieties have the variable resistance to stress. In this study, “Undulated leaf” genotype was more resistant compared to “Entire leaf”. So, it can be cultivated in gardens in areas where the water scarcity is prevalent.
Seyed marziyeh Hosseini valashkolaee; Yahya Tajvar; Masoud Azadbakht; Zeinab Rafie-rad
Abstract
Low temperature stress is one of the most important abiotic environmental stresses that affects the growth and yield of ornamental plants. In order to investigate of some physiological and biochemical indices of four varieties of ornamental Citrus used in urban landscapes under low temperature stress ...
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Low temperature stress is one of the most important abiotic environmental stresses that affects the growth and yield of ornamental plants. In order to investigate of some physiological and biochemical indices of four varieties of ornamental Citrus used in urban landscapes under low temperature stress conditions, a factorial experiment in a completely randomized design with three replications was conducted in the Citrus and Subtropical Fruits Research Center of Ramsar in 2015. Treatments were included the temperature with four levels (3, 0, -3 and -6˚C) and four varieties of ornamental Citrus including (Kumquat, Fingered citron, Calamondin and Limequat). Results showed that amounts of electrolyte leakage, water soaking, prolin content, antioxidant capacity, lipid peroxidation and superoxide dismutase activity were increased significantly by reducing of temperature, while chlorophyll and total chlorophyll contents were decreased. Accordingly, the lowest leaf water soaking (20.92%) and electrolyte leakage (30.81%) amount, which are destructive indices, were showed in Kamquate. Total chlorophyll amount (2.21 mg/gFW), antioxidant capacity (60.61%) and superoxide dismutase activity (26.53 IU/gFW), that are tolerability indices, were more relevant at Kamquate. In general, Kumquat could tolerate the freezing stress up to -3°C by increasing of some indices such as proline, soluble sugars, antioxidant capacity and superoxide dismutase activity.
masoud arghavani; Saeedeh Savadkoohi; Seyed Najmadin Mortazavi
Abstract
This experiment was conducted in order to investigate morphological and physiological responses of Kentucky bluegrass (Poa pratensis L.) to salinity and silicon application in horticultural science department at the University of Zanjan in 2015. The salinity levels (0, 40 and 80 mM NaCl) and sodium silicate ...
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This experiment was conducted in order to investigate morphological and physiological responses of Kentucky bluegrass (Poa pratensis L.) to salinity and silicon application in horticultural science department at the University of Zanjan in 2015. The salinity levels (0, 40 and 80 mM NaCl) and sodium silicate (0, 0.75 and 1.5 mM) were applied in complete nutrient solutions. Salinity reduced root and shoot growth, visual turf quality, leaves chlorophyll and potassium content, whereas electrolyte leakage, proline and sodium content increased with increasing salt concentration in nutrient solution. Silicon application ameliorate adverse effects of salinity in all factors except in potassium content and this effect was more pronounced in 80 mM NaCl. Although there was no significant difference between 0.75 and 1.5 mM sodium silicate in visual turf quality, root growth and chlorophyll content, altogether, application of 1.5 mM silicon had better results to increase salinity tolerance in Kentucky bluegrass, suggesting that higher concentrations of silicon must be evaluated.
Mahshid Ghafouri; Ali Soleimani; Vali Rabiei
Abstract
Using the essential oils to increase the storage life and quality of horticultural products as a new idea is developed in agriculture. In this context, an experiment was conducted in order to effect of application Essential oils of clove and Cinnamon on maintain quality post-harvest of pomegranate (‘Punica ...
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Using the essential oils to increase the storage life and quality of horticultural products as a new idea is developed in agriculture. In this context, an experiment was conducted in order to effect of application Essential oils of clove and Cinnamon on maintain quality post-harvest of pomegranate (‘Punica granatum’ cv. Tarom red skin). A split design in time in a completely randomized design with two factors essential oils of cloves and cinnamon each in four levels (0, 500, 1000, 1500 mg per liter) and time in three levels (one month, two months, three months of storage) at 6°C and relative humidity of 85 percent, with four replications. The results showed that with increasing storage period total soluble solid (TSS), anthocyanin, electrolyte leakage, chilling injury, weight loss percent and severity of decay increased. Essential oils by reducing oxidation processes, such as respiration of consumption organic acids in products reduce. The amount of anthocyanin in the fruit treated with essential oil of clove increased more than pomegranates treated with Essential oil of cinnamon. Essential Oils of clove and Cinnamon have a similar effect of chilling injury and decay. Decay of (42.25 percent) in control to (30.75 percent) in the essential oil of cloves 1500 mg per liter decreased in the second month of storage. General, pomegranates treated with essential oils of clove and essential oil of cinnamon have better quality and storage life.
Roya Karimi; Hashem Hadi; Mehdi Tajbakhsh Shishavan
Abstract
According to the global water shortage problem, the exploring for reducing its harmful effects is very important. This experiment was conducted as split plots method based on randomized complete block design with three replicates in Urmia University research field during growing season of 2013-14. Water ...
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According to the global water shortage problem, the exploring for reducing its harmful effects is very important. This experiment was conducted as split plots method based on randomized complete block design with three replicates in Urmia University research field during growing season of 2013-14. Water deficit stress as main plot consisted of three levels (irrigation when soil moisture reached 90, 70 and 50 percent of soil field capacity) and foliar applications (at 5-6 leaf stage two times with an interval of three days) as sub plot with five levels including: no foliar application (control), foliar application of salicylic acid (0.5 and 1 millimolar) and zinc sulphate (300 and 3000 milligram per liter). The results showed that the interaction effect of foliar application and water deficit significantly influenced photosynthetic pigments (except total chlorophyll content) and relative water content. The main effects of foliar application and water deficit were significant on leaves number, dry weight of leaves and stems, forage yield per square meter, electrolyte leakage and leaf area index. Severe Water deficit significantly decreased dry matter yield by 21.11 percent relative to normal irrigation. The maximum forage dry matter yield with average of 1571.53 gram per square meter were produced by both foliar application of zinc sulphate 3000 milligram per liter and salicylic acid 0.5 millimolar, which not only compensate for spraying costs but also lead to an acceptable increase in farmers' income. Therefore they could be recommended for farmers.
Saloomeh Taheri; Taher Barzegar; Vali Rabiei; Hossein Rabi Angoorani
Abstract
Salinity is one of the most important environmental stresses that affect plant growth. In order to study the effect of Salicylic Acid (SA) on some physiological characteristics of basil under salinity conditions, the experiment was set out as a factorial design in the base of RCBD with three replications. ...
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Salinity is one of the most important environmental stresses that affect plant growth. In order to study the effect of Salicylic Acid (SA) on some physiological characteristics of basil under salinity conditions, the experiment was set out as a factorial design in the base of RCBD with three replications. Treatments consisted of four NaCl salinity levels (0, 50, 100, 150 mM), salicylic acid at three levels (0, 0.25, 0.5 mM) and two cultivars of basil (purple and green). Results showed that salinity significantly decreased amount of chlorophyll, carotenoid and leaf relative water content. Application of SA increased amounts of chlorophyll, carotenoid and leaf relative water content. The amount of proline, stomatal resistance and electrolyte leakage in leaves increased significantly under salinity condition and decreased with treatment of salicylic acid. The highest amount of chlorophyll b (0.617 mg/g FW-1) and the minimum electrolyte leakage (30.4 percent) was observed with application of 0.5 mM SA under of 0 mM NaCl concentration in green and purple basil cultivars, respectively. Also, the maximum content of proline (11.4 µg/g FW-1) and the lowest rate of stomatal resistance (7.8 s/cm-2) were obtained under 150 mM NaCl in purple and green basil cultivars, respectively. According to the results, application of salicylic acid can be proposed to improve plant growth under salinity conditions.
Shiva Bazl; Rouholah Karimi; Ahmad Ershadi; Alireza Shahbodaghlo; Mousa Rasouli
Abstract
Cold stress is one of the limiting factors in production of greenhouse vegetables. Chemicals offer useful approach to reduce low temperature-induced damages. This study was conducted to evaluate the effect of foliar application of methyl jasmonate (MeJA) at concentrations of 0 (control), 50, 100, 200 ...
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Cold stress is one of the limiting factors in production of greenhouse vegetables. Chemicals offer useful approach to reduce low temperature-induced damages. This study was conducted to evaluate the effect of foliar application of methyl jasmonate (MeJA) at concentrations of 0 (control), 50, 100, 200 µM) on electrolyte leakage (EL), relative water content (RWC), soluble carbohydrates, proline, chlorophyll content and chilling index of greenhouse- grown cucumber (Cucumis sativus L. cv ‘Negin’) in 4-6 leaf stage. MeJA was sprayed two times/day on cucumber seedling in a greenhouse of Bu-Ali Sina University, as a factorial based on completely randomized design with five replications per treatment, inlate- summer of 2013. Two days after spraying, seedlings were transferred from 25ºC to cold chamber and were subjected to chilling treatments of 15, 10 and 5 ºC for 4 hours. The EL of all plants increased with reducing the temperature. However, in MeJA-treated plants, especially in application of 200 µM, a lower leaf EL was observed. A clear increase in soluble carbohydrates and proline concentration was observed with decreasing temperature from 15 to 5ºC in all plants while in MeJA -treated seedlings, especially in application of 200 and 100µM, a greater amount of these osmolytes were observed in compared to control. Moreover, exogenous application of MeJA reduced RWC and visual damage of cold-stressed seedlings but increased chlorophyll content in compared to control plants. These changes correlated with the increment of cold tolerance in the cucumber plants. The results indicated that MeJA application especially at 200 µM, has the capacity to improve chilling tolerance of seedlings and can be used as a prophylactic tool to protect against chilling injury of cucumber cultivars in greenhouses
Forough Saydpour; Mohammad Sayyari; Fardin Ghanbari
Abstract
Glycine betaine (GB) is one of the osmotic plant-protecting members that accumulate in response to abiotic stresses. An experiment was, therefore, conducted to test whether GB application at various concentrations (0, 10, 20 and 30 mM) through seed soaking or foliar spray methods would protect cucumber ...
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Glycine betaine (GB) is one of the osmotic plant-protecting members that accumulate in response to abiotic stresses. An experiment was, therefore, conducted to test whether GB application at various concentrations (0, 10, 20 and 30 mM) through seed soaking or foliar spray methods would protect cucumber seedlings, subjected to chilling stress. At two true leave stages, after GB treatment, the seedlings were exposed to chilling six h/day at 3°C for 6 days. Results showed that GB pre-treatment improved growth parameters of seedlings subjected to chilling stress and provided significant protection against chilling stress compared to non-GB-treated seedlings. GB prevented chilling injuries with increasing chlorophyll, proline content and antioxidant activities and decreasing electrolyte leakage, malondialdehyde and hydrogen peroxide content. The highest cold tolerance was obtained with 20 and 30 mM GB application and seed soaking method provided better protection compared to foliar spray method.
Ahmad Ershadi; Samira Taheri
Abstract
Frost in early spring is one of the limiting factors in the production of grape. Chemicals offer useful approach to reduce low temperature-induced damages. Different concentrations of salicylic acid including: 0 (control), 0.5, 1 and 2 mM were sprayed twice on 10 year-old ‘Bidaneh Sefid’ ...
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Frost in early spring is one of the limiting factors in the production of grape. Chemicals offer useful approach to reduce low temperature-induced damages. Different concentrations of salicylic acid including: 0 (control), 0.5, 1 and 2 mM were sprayed twice on 10 year-old ‘Bidaneh Sefid’ grape vines at full bloom stage and changes in leaf soluble carbohydrates, proline and protein levels were measured in the next day morning. Leaf and stem samples were subjected to low temperatures of 0, -2, -4 and -8°C while flower clusters were exposed to temperature of 0, -2 and -4°C for three hours. Salicylic acid at 0.5mM concentration resulted in the highest amounts of soluble carbohydrates while the maximum proline content was observed with 0.5 and 1mM concentrations. Salicylic acid at 2mM concentration caused a decrease in soluble protein level. Salicylic acid, low temperature and their interactions had a significant effect on electrolyte leakage of different tissues. Salicylic acid treatments led to a reduction in electrolyte leakage of stem, leaf and cluster samples, compared to control. It seems that salicylic acid minimizes the negative effects of low temperature with evidence of less membrane damage by up-regulating the accumulation of osmoregulants such as soluble carbohydrates and proline.
Kamran Amiri Nasab; Hedayat Zakizadeh; Mahmoud Ghasemnezhad; Hassan Biglouei
Abstract
Drought preconditioning (DP) is a method of irrigation with low frequency and longer duration, to extend the root system and suppress drought damage in plants. In the present study, the effect of DP for 30 days on increasing tolerance to drought stress in two turfgrass species, creeping bentgrass (Agrostis ...
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Drought preconditioning (DP) is a method of irrigation with low frequency and longer duration, to extend the root system and suppress drought damage in plants. In the present study, the effect of DP for 30 days on increasing tolerance to drought stress in two turfgrass species, creeping bentgrass (Agrostis stolonifera cv.Palustris) and tall fescue (Festuca arundinacea cv. Greystone) was investigated. DP and control plants were irrigated for 50 days with different levels of soil suction (20-23,40-43, 50-53 and 70-73 centibar), and finally, plants were watered up to field capacity point for 15 days, to recover from stress. Results showed that DP significantly lead to reduction in shoot length and increase in root length in both turfgrass species. DP plants showed less shoot dry and fresh weight and also less electrolyte leakage (EL) at each levels of stress, in compare with the control. Furthermore, DP plants showed greater reduction in EL after recovery. DP treatment also reduced leaf RWC at the end of 50 days of stress and after recovery in tall fescue, but in creeping bentgrass retained it at the control level. Overall, it appears that DP treatment can increase tolerance to drought stress in two species with increasing root length, reducing shoot length and EL and preserving leaf RWC.