Mahdi Yaghoobi; Mahdi Parsa; Ali Gazanchian; Hamidreza Khazaie
Abstract
Introduction: Lack of water resources is one of the most problems ofincreasing urban green spaces. Over the last threedecades, turfgrass and lawn researches have put significant effort into developing and evaluating turf species that have good drought resistance. As water conservation becomes an important ...
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Introduction: Lack of water resources is one of the most problems ofincreasing urban green spaces. Over the last threedecades, turfgrass and lawn researches have put significant effort into developing and evaluating turf species that have good drought resistance. As water conservation becomes an important issue, considerable interest is increasing in identifying grasses that require less water. Plants with good drought resistance are those that are able to survive stress by means of drought avoidance, drought tolerance at leaf water potentials, or both. The efficient use of water is made possible by understanding the effects of irrigation water on crop development and yield. Drought affects the visual quality, growth rate and evapotranspiration. Researchers reported that turfgrass subjected to drought conditions for short periods could sustain a fairly good appearance by irrigation about half of its consumptive use whenever soil moisture level falls to near permanent wilting point. Drought stress caused decrease in RWC and visual quality of many grass cultivars. In drought conditions resistance grass showed increase in proline content on their leaves. Therefore the use of native grasses with high-strength instead of grass imported with low-resistance is one way to increase green space and reduce costs. The purpose of this study was comparednative grasses with commercial grass cultivars.
Materials and Methods: This study was to evaluate the yield and resistance of native grasses to drought stress in 2014. This experiment was conducted in Khorasan Agricultural Research Center. NativeAgropyron grass species includedAgropyronelangatum, A. desertrum, A. cristatum and commercial cultivarwassuper sport and third level of stress, including severe stress (45% FC), moderate stress (65% FC) and control (85% field capacity) were experimental treatments. Plants were cultured in PVC containers measuring 9 cm in diameter and 60 cm deep under greenhouse condition. Soil was mixture of 70% loam soil, 20% pit mass and 10% sand. Greenhouse air temperature was maintained between 22 and 28 centigrade degree. All plants were maintained under well watered conditions for 45 days before drought stress. This experiment was designed in factorial experiment based on completely random with fourreplicates. After the stress treatment parameters such as length and width of leaves, chlorophyll a, chlorophyll b and total chlorophyll content, visual quality, electrolyte leakage, RWC and proline content of leaves were measured. Length and width of leaves were measured with ruler. Proline content, RWC percent, chlorophyll a, chlorophyll b and total chlorophyll content of leaf, visual quality and leaf electrolyte leakage weremeasured with standard protocols. Analysis of the data by statistical software JMP 8 and graphs with Excel 2010 was drawn.
Results and Discussion: Result of the experiment showed that those native species have different response to soil moisture stress conditions. The highest and lowest lengths of leaf were observed under45% field capacity in A. elangatum and super sport grass, respectively. The results showed that width of leaves of A. elangatum increase and then decrease in super sport. Under drought stress conditions A. desertrum has best visual quality with 6.07 score. Highest chlorophyll a and total chlorophyll were observed in A. elangatum. The lowest electrolyte leakage under drought stress was obtained from A. elangatum with 17.91 percent. RWC content in the native A. elangatum increased to 82.12 compared with super sport (control). A. elangatum under drought stress showed highest proline content and commercial cultivar (super sport) indicated lowest proline content at 45% field capacity irrigation. Selahvarzi and et al. (2009) found that visual quality of tall fescue decrease in drought stress. In drought stress, RWC percent decrease in grass species. Proline content was increasedupondrought stress inLoliumperenecool season grass. Many studies on native cultivar indicated that native turfgrass cultivar have more resistance to drought stress compared with exotic turfgrass cultivars.
Conclusions: According to the results, we said native grass species under drought stress conditions have better quality compared with imported grass cultivar such as Super sport. Visual quality in native grass was suitable for use in urban landscape, that visual quality show little change in drought stress and leaves were fresh in this conditions. The best visual quality of two native species A. elongatum and A. desertrum was observed under 65% field capacity. Nativegrass cultivars were more resistance than imported grass cultivars. This study showed that native grass such asA. elongatum and A. desertrumhas low cost to use and these turfgrass need to lower water irrigation than commercial grass Super sport. Then two species can be introduced as low-input cultivars.
Mehdi Aran; Bahram Abedi; Ali Tehranifar; Mehdi Parsa
Abstract
Introduction: Most plants have developed morphological and physiological mechanisms which allow them to cope with drought stress. Almost all the studies conducted on grapevines (Vitisvinifera L.) responses to drought conditions have focused on physiological responses such as stomatal reactions, photosynthesis ...
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Introduction: Most plants have developed morphological and physiological mechanisms which allow them to cope with drought stress. Almost all the studies conducted on grapevines (Vitisvinifera L.) responses to drought conditions have focused on physiological responses such as stomatal reactions, photosynthesis and osmotic adjustment, and biochemical responses like carbohydrates and proline. According to these studies, physiological and biochemical responses of grapevines to water stress are quite variable. This variability could be related to cultivar, time of the year, previous water stress level, intensity of stress, and environmental conditions. Osmotic adjustment in terms of compatible solutes accumulation has been considered as an important physiological adaptation for plant to resist drought, which facilitates the extraction of water from dry soils and maintenance of cell turgor, gas exchange and growth in very dry environments. Acting as compatible solutes as well as antioxidants, a significant rise in proline amount was observed in grapevine leaves under water stress conditions, suggesting that this amino acid has a protective role against the formation of excessive reactive oxygen species (ROS). Plants, in order to overcome oxidative stress, have developed enzymatic and non-enzymatic antioxidant defense mechanisms against scavenge ROS.
Materials and Methods: This research was conducted to assess the effect of different levels of irrigation on some characteristics of three cultivars of grapevine (Yaghooti, Bidanesefid and Askari), as a factorial based on a randomized complete block design in two years with four replications. The experiment started in June 21, 2014 and 2015. Water treatments were applied in four levels including: control plant (100% FC), moderate stress (60% FC), severe stress (30% FC) and rewatering treatment after severe stress treatment. Increase height, leaf number, stem diameter, leaf fresh and dry weight, stem dry weight, chlorophyll index,RWC, electrolyte leakage, soluble sugar, antioxidant activity, phenolic compound and proline were measured at the end of the experiment. JMP8 software was used to test the significant differences among the treatments and the interactions. When there were significant differences, means were separated by Tukey HSD test at the probability level p
Naser Abbaspour; Lavin Babaei; Alireza Farrokhzad
Abstract
Introduction: Water stress is considered as a main environmental factor limiting crop growth and yield, including grape in Mediterranean areas.Selection for drought-tolerantvarieties is possible through investigation of their performance under stress conditions. The estimation of physiological characteristics ...
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Introduction: Water stress is considered as a main environmental factor limiting crop growth and yield, including grape in Mediterranean areas.Selection for drought-tolerantvarieties is possible through investigation of their performance under stress conditions. The estimation of physiological characteristics as reliable indices can be used as a tool to select tolerant plants. For this reason, varieties and genotypes of one plant species are usually investigated through physiological characteristics and its relation to drought tolerance. Investigation of the effects of water stress on some growth and physiological characteristics in grape plants has revealed that plant height, number of leaves and nodes, leaf area and the percentage of dry weightdecreased under increasing drought stress. Salicylic Acid is a naturally occurring plant hormone whichinfluences various morphological and physiological functions in plant. It can act as an important signaling molecule and has diverse effects on biotic and abiotic stresses tolerance capacity.
Materials and Methods: In this research, two-yearold grapesplanted in plastic pots containingingredients of humus, soil and sand (1:2:1) were used. The experiment was conducted using a factorial based on randomized complete block design with three factors including irrigation periods (every 5, 10 and 15 days), salicylic acid concentrations (0, 1 and 2 mM) and grape cultivars (Rasheh andBidanesefid) with 3 replications in thegreenhouse of faculty of agricultureinUrmia University. Plant height, stem diameter and leaf area and chlorophyll indicesweremeasuredby usingruler, digital caliper (Model22855 NO: Z), leaf Area Meter (ModelAM200) and SPAD-502 chlorophyll meter (Minolta Crop, Japan),respectively. In order to determine proline content, malondialdehyde (MDA), total protein and total soluble sugars, spectrophotometric methods [51,25,6and28] were utilized,respectively.
Results and Discussion: Based on comparing the averages related to the interaction of various levels of drought and salicylic acid, increasing watering intervals resulted in significant decrease in parameters of plant height, stem diameter, leaf area, leaf number and chlorophyll index,and increase inproline content, malondialdehyde, total protein and total soluble sugars.Furthermore, according to the obtained results, plant height, stem diameter, leaf number, chlorophyll index, accumulation of prolineandtotal protein in grape cv. Rashehwere higher than Bidanesefidone.Drought effected the mitotic division, andelongation and expansion of cells, leading to reduced growth and crop yield. It was concluded that plant height, stem diameter, and leaf area decreased noticeably byincreasing water stress. The reduction in plant height could be attributed to decline in the cell enlargement and higher rate ofleaf senescence in the plant under water stress. The reduction in leaf number under severe water deficit was partially due to leaf senescence. Reduction inthe number of leaves could be a response by plants to minimize the transpiration surface. Sorghum plants have also been reported to have a similarbehaviorthroughwhichthey conserve water by reducing the number of leaves. When exposed to chronic water deficit, they showed an initial decrease in the daily increment of leaf area and eventually a decrease due to accelerated senescence. Dropping of the leaves during severe stress markedly reduces the evaporative surface and allows the plant to conserve water.It is well known that proline contents in leaves of many plants are enhanced by several stresses including drought stress. The efficiency of exogenous SA depends on multiple causes such as the species, developmental stage of the plant, manner of application and concentration of SA.Plant height, stem diameter, leaf number, leaf area, leaf total soluble sugar and chlorophyll index increased by applying 2 mM salicylic acid comparedwith 0 and 1 mM doses. The findings of this study showed that salicylic acid was able to enhance the tolerant capacity of the grape plant to the drought stress. According to theobtained results, Rashehcultivar showed a greater resistance to drought stress. Salicylic acid prohibits auxin and cytokinin loss in plants and thus enhances cell division and plant growth. Salicylic acid maintainsphotosynthetic aspects like chlorophyll content at proper level and thus helps plants to grow and developwell. In this study, the drought stress increased the amount of MDA.MDA and other aldehydes in the dry conditions are the result ofactive oxygen species (ROS) such as super oxide radical, peroxide, hydrogen and radical hydroxide, whichareproduced underoxidative stress conditions. The species of active oxygen leads to lipids' per oxidation as a result of injury or damage to the cellular membrane, especially chloroplast membrane.Salicylic acid increases the activity of antioxidant enzymes such as CAT, POD and SOD which in turn protect plants against ROS generation and lipid peroxidation. Salicylic acid treatment also providesa considerable protection from the enzyme nitrate reductase, thereby maintaining the level of diverse proteins in leaves.Mohammadkhani and Heidari (48) found that the initial increase in total soluble proteins during drought stress was due to the expression of new stress proteins.
Ramin Mahdavi; Madhi Parsa; Ali Gazanchian; Hamidreza Khazaie
Abstract
Introduction: Over the last three decades, turfgrass breeders have put significant effort into breeding and developing turf species that have good drought resistance. As water conservation becomes an important issue, an interest is increasing in identifying grasses that require less water. Lack of water ...
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Introduction: Over the last three decades, turfgrass breeders have put significant effort into breeding and developing turf species that have good drought resistance. As water conservation becomes an important issue, an interest is increasing in identifying grasses that require less water. Lack of water resources is most problems to increasing urban green spaces. Plants with good drought resistance are those that are able to survive stress by means of drought avoidance, drought tolerance at leaf water potentials, or both. The efficient use of water is made possible by understanding the effects of soil moisture water on crop development and yield. Drought affects the visual quality, growth rate and evapotranspiration. Researchers reported that turfgrass subjected to drought conditions for short periods could sustain a fairly good appearance by soil moisture about half of its consumptive use whenever soil moisture level falls to near permanent wilting point. Drought stress caused decrease in RWC and visual quality of many grass cultivars. In drought conditions resistance grass showed increase in proline content on their leaves. Therefore the use of native grasses with high-strength instead of imported grass with low-resistance is one way to increase landscape areas and reduce costs. The purpose of this study was to be compared native grasses with commercial grass cultivar “Super sport”.
Materials and Methods: The objective of this study was to evaluate the effect of soil moisture stress levels included 85% (control), 65% and 45% of field capacity on native species Brumos tomentellus, Festuca rubra and F. arundinacea and commercial cultivars Super sport (control) under greenhouse conditions. Plants were cultured in PVC containers measuring 9 cm in diameter and 60 cm deep. Soil was mixture of 70% loam soil, 20% pit mass and 10% sand. Greenhouse air temperature was maintained between 22 and 28 centigrade degree. All plants were maintained under well watered conditions for 45 day before drought stress. This experiment was conducted as factorial experiment based on completely random design with four replications. Measured parameters were length and width of leaves, chlorophyll a, chlorophyll b and total chlorophyll content, visual quality, electrolyte leakage, RWC and proline content of leaves. Length and width of leaves measured with ruler. Proline content, RWC percent, chlorophyll a, chlorophyll b and total chlorophyll content of leaf, visual quality and leaf electrolyte leakage was measured with standard protocols. Analysis of the data by statistical software JMP 8 and graphs with Excel 2010 was drawn.
Results and Discussion: Result of the experiment showed those native species have different response to soil moisture stress conditions. The highest and lowest length of leaves were observed in 65% field capacity in F. arundinacea and super sport grass, respectively. The results showed that width of leaves of B. tomentellus increased and decreased in super sport. Under soil moisture stress conditions, F. arundinacea has best visual quality with 7.66 score. Highest chlorophyll a and total chlorophyll were observed in tall fescue grass. The lowest electrolyte leakage under drought stress was obtained from F. rubra with 25.66 percent. RWC content in the native F. arundinacea increased to 77.80 compared with super sport (control). B. tomentellus under soil moisture stress showed the highest proline content and commercial cultivar (super sport) indicate lowest proline content at 45% field capacity. Selahvarzi and et al. (2009) found that visual quality of tall fescue decrease in drought stress. In drought stress RWC percent decrease in grass species. Proline content was increased in drought stress at Lolium perene cool season grass. Much studies on native cultivar indicated that native turfgrass cultivar have more resistance to drought stress compared with exotic turfgrass cultivars.
Conclusions: According to the results, we said native grass species under drought stress conditions have better quality compared with imported grass cultivar Super sport. Visual quality in native grass were suitable for use in urban landscape, that visual quality showed little change in soil moisture stress and leaves were fresh in this conditions. Native grass cultivars were more resistance than imported grass cultivar. This study showed that native grass such as F. arundinacea and F. rubra has low cost to use and these turfgrass need to lower water soil moisture than commercial grass Super sport.
Fateme Hasanvand; Abdolhossein Rezaeinejad; Mohammad Feizian
Abstract
Introduction: Scented geranium (Pelargonium graveolens) is a perennial plant of the family Geranium (Geraniaceae). Although CaCl2 at higher concentrations than NaCl in the soils and ground water in many areas of the word, most studies have been based on experiments that NaCl is the predominant salt. ...
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Introduction: Scented geranium (Pelargonium graveolens) is a perennial plant of the family Geranium (Geraniaceae). Although CaCl2 at higher concentrations than NaCl in the soils and ground water in many areas of the word, most studies have been based on experiments that NaCl is the predominant salt. Relatively few studies have focused on the effects of CaCl2 on plant growth and physiology. Silicon (Si) is considered as an essential element in several crops enhancing growth and alleviating different biotic and abiotic stresses. In this study, the role of Si in alleviation the deleterious effects of salinity on geranium have been studied.
Materials and Methods: This experiment was conducted in spring-summer 2014 in research greenhouse situated on the Faculty of Agriculture, Lorestan University, Khorramabad, Iran. The greenhouse temperature was 16.5–37.5 ◦C and relative humidity of greenhouse was 30–80%. Terminal stem cuttings with five nodes were obtained from mother plants in the same greenhouse and placed in a sand substrate for rooting in April. Uniform rooted cuttings were then transplanted into plastic pots (22 cm diameter and height) filled with sand substrates and grown hydroponically. Transplanting was done in May and one plant per pot was cultivated. Cultivated plants were irrigated with Hoagland’s medium electrical conductivity (EC) 1.8 dS/m, (pH) 5.8 twice a day. Experiment was arranged as factorial based on a completely randomized design with five replications. Factors consisted of daily application of 1.8, 4 and 6 ds/m CaCl2 and weekly application of 0, 0.5 and 1 mM silicic acid in nutrient solution. Plants were harvested in November. In this research some characteristics include the number of leaf, leaf area, photosynthetic pigments (chla, chlb. Total chl, carotenoids), MDA, EL, RWC, proline, number of stomata in surface unit of leaf, density of stomata and stomata index and antioxidant enzyme include CAT and POD measured.
Results and Discussion: In current study salinity decreased the number of leaf and leaf area and Si increased these characteristics. In general, decrease in the leaf area can result in a reduction in size of individual leaf of plants, decrease in the production of leaves and fall the old leaves. It also reduce the growth rate of leaf in salinity which causes osmotic effect around the roots (rhizosphere). Over time, the rate of cell division and elongation decreased, and finally this changes leads to decrease in the final size of leaf. In this study, salinity increased electrolyte leakage and the use of silicic acid prevents electrolyte leakage. Probably saturation of phospholipids with increasing salinity increased, as a result the fluidity of membrane decreased and finally increased the electrolyte leakage, silicic acid absorbed in plant and deposited in the cell membrane, causing the silica hardened. This causes in stress condition, cell membrane maintains stability and significantly reduced the amount of electrolyte leakage. In this study application Si in various concentrations under salinity stress brought a significant decrease in MDA compared with salinity alone. Salinity increased the MDA and EL so that application of1 mM silicic acid decreased EL to 16.7 and 11.9 percent plants grown in 4 and 6 dS/m EC, respectively, compared with controls. Application of 1 mM silicic acid decreased the MDA to 23.6 and 35 percent plants grown in 4 and 6 dS/m EC, respectively, compared with controls. Therefore, the present results indicate that Si can effectively ameliorate membrane lipid peroxidation, thus protecting plants from oxidative stress. Salinity affected on leaf anatomy and chloroplast ultrastructure, photosynthesis also affected by these factors. Reduction in chlorophyll at height salinity levels due to chloroplast destructive. The results showed that salinity decreased the density and stomatal index in plants and silicic acid increased these characteristics. Salinity decreased the RWC and antioxidant enzymes and application of silicic acid improved them. Increase in salinity increased the leaf proline and application of silicic acid alone in plant on stress decreased it.
Conclusion: Overall, the results of present research showed that high EC induced by CaCl2 negatively affected geranium growth, and weekly application of 1 mM silicic acid alleviated the destructive effects of stress and in high salinity the positive effect of silicic acid is more than in low salinity.
Shadan Khorshidi; Gholamhossein Davarynejad; Leila Samiei; Mohammad Moghaddam
Abstract
Introduction: Most deciduous trees need low temperature to break flower bud dormancy. One of the most important abiotic stresses is low temperature which limits production of temperate fruits. Pear production has been considerably reduced in recent years. Important pear cultivars show different levels ...
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Introduction: Most deciduous trees need low temperature to break flower bud dormancy. One of the most important abiotic stresses is low temperature which limits production of temperate fruits. Pear production has been considerably reduced in recent years. Important pear cultivars show different levels of resistance to cold. Cold compatibility followed by resistance increase is controlled genetically and contains several mechanisms which lead to production of different metabolites such as: polypeptides, amino acids and sugars. The object of this research was to evaluate the frost resistance of different ‘Dare Gazi’ genotypes and other pear cultivars in Mashhad climate condition.
Materials and Methods: This study was conducted to investigate the frost resistance of 23 ‘Dare Gazi’ pear genotypes and nine other cultivars include: ‘William’s’, ‘Bell de june’, ‘Spadona’, ‘Koshia’, ‘Domkaj’, ‘Torsh’, ‘Sebri’ and ‘Tabrizi’. Plant material contained vegetative and reproductive buds of one-year-old shoot samples which were collected from 25-year old trees on March 2014, four days after winter cold (-6.6 °C) in three directions of trees and sent to the laboratory. Frost damages of vegetative and reproductive buds were investigated based on visual observations (%), electrolyte leakage (EC) and proline content. EC was measured with a Metrohm 644 digital conductivity meter and proline content was measured based on Bates et al. (1973) method, using acid ninhydrin. The experiment was performed on completely randomized experimental design with three replications. Statistical analysis was carried out using MSTAT-C and Excel software. Mean values were compared using the least significance difference test (LSD) at 1% levels. Cluster analysis was conducted by SPSS 16 program.
Results and Discussion: Highest EC of reproductive buds was observed in ‘Dare Gazi’ 10, 19, ‘Tabrizi’ and ‘Torsh’ whereas ‘Dare Gazi’ 8, 18 and ‘Bell de June’ had the lowest EC. Based on visual observations, the least percentage of damaged reproductive buds was observed in ‘Dare Gazi’ 22 while ‘William’s’ suffered from frost at the highest damage level (96%). Göndör and Tóth (1998) studied 13 pear cultivars by microscopic observations of flower buds and found that ‘Packham's Triumph’ was relatively resistant under Hungarian ecological conditions. Honty et al. (2008) reported that Kaiser was the most sensitive pear cultivar to low temperatures during endodormancy and ecodormancy. Khorshidi et al. (2014) described that pear reproductive buds of ‘Ghodumi’ were the most tolerant. Considering the vegetative buds, ‘Dare Gazi’ 19 had the highest EC (74.47 %) which was not significantly different from ‘Dare Gazi’ 10, 20 and 3 whereas the lowest one was found in ‘William’s’(24.75%). The highest percentage of healthy vegetative buds was found in ‘Dare Gazi’ 1 (50%) which did not show a significant difference with ‘Dare Gazi’ 12, 5 and 7. ‘Tabrizi’ was the most sensitive and had most damaged vegetative buds (95.99%). Khorshidi et al. (2014) observed the least damaged vegetative buds in ‘Dare Gazi’ and the most damaged buds in ‘Boheme’ and ‘Ghodumi’. Palonen and Buszard (1997) mentioned that hardiness of woody tissue of apples did not seem related to flower bud hardiness. The highest proline content of reproductive buds was found in ‘Dare Gazi’ 20 (21.28 µmol g-1FW) and the lowest content observed in ‘Dare Gazi’ 2 (0.1 µmol g-1 FW). Young (1977) described that increase in proline was not correlated well with relative cold hardiness of citrus rootstocks. Data did not show any significant correlation between EC and proline content. Barka and Audran (1997) studied grape buds and shoots and reached a high negative correlation between proline content and frosttolerance. Yelonsky (1979) indicated that accumulation of proline was not correlated to cold hardiness. The results of present experiment were in agreement with Duncan and Jack (1987) findings which reported that increase in proline was not always correspondent to cold resistance. Based on the cluster analysis, the genotypes laid in two distinct groups. First group included ‘Dare Gazi’1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 17, 18, 19, 20, 23 and ‘Sebri’, ‘Domkaj’, ‘Bell de june’ and ‘Koshia’ and second group include ‘Dare Gazi’ 11,16, 21 and ‘William’s’, ‘Spadona’ and ‘Torsh’. Frost damage, EC and proline content were higher in the first group compared to second group.
Conclusion: Cosidering‘DareGazi’ genotypes, no correlation was found between proline content and frost damage rate. This shows that morphological differences among ‘Dare Gazi’ genotypes could be due to the existing of genetic variation of these genotypes or they are different clones of one cultivar.
Sarah Bakhtari; Gholam Reza Khajoei Nejad; Ghasem Mohamadi Nejad; Rooholla Moradi
Abstract
Introduction: Medicinal plants play major roles in human health. . Cumin (Cuminum cyminum L.) is an annual plant that commonly cultivated in arid and semiarid regions of Iran. The crop has a wide range of uses including medicinal, cosmetic and food industry. Cumin occupies about 26% of the total area ...
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Introduction: Medicinal plants play major roles in human health. . Cumin (Cuminum cyminum L.) is an annual plant that commonly cultivated in arid and semiarid regions of Iran. The crop has a wide range of uses including medicinal, cosmetic and food industry. Cumin occupies about 26% of the total area devoted to medicinal plants in Iran. However, cumin is seriously affected by the Fusarium wilt and blight diseases. The diseases usually increase under warm and wet conditions. It was demonstrated that the peak of the disease incidence is occurring at the flowering stage and irrigation cutoff at this time may be reduced the diseases density.
Materials and methods: In order to evaluate the effects of irrigation cutoff in flowering stage and foliar application of spermidine on some characteristics of various ecotype of cumin, an experiment was conducted in a split-split-plot arrangement in randomized complete block design with three replications at the research farm of Shahid Bahonar University of Kerman at 2014. The experimental treatments were irrigation in two levels (complete irrigation and cutoff the irrigation in flowering stage) assigned to main plots, foliar application of spermidine in three levels (0, 1 and 2 Mm) as a subplot and cumin ecotypes in three levels (Kerman, Khorasan and Esfahan) that was randomized in sub-subplot. Plots size under the trial was 4 m × 3 m so as to get 50 cm inter row spacing in six rows. The ideal density of the crops was considered as 120 plant m-2. As soon as the seeds were sown, irrigation was applied every 10 days. Foliar application of spermidine was done at three stages (after thinning, before flowering stage and in the middle of flowering stage). No herbicides and chemical fertilizers were applied during the expriments.
Results and discussion: In this study the number of branches, umbels per plant, 1000-seed weight, seed yield per plant and hectare, harvest index, essential oil percentage and yield, infected plants and proline contents were assessed. The results showed that irrigation treatment had a significant effect on all the studied traits except number of branches and umbels per plant. The irrigation cutoff at flowering stage caused a significant increase in seeds per umbel, infected plants and seed yield per plant and hectare Whereas harvest index, essential oil percentage and yield and proline contents were higher in irrigation cutoff treatment compared to completely irrigated treatment. The value of decrease in seed yield per hectare as affected by irrigation cutoff was so lower than that per plant; because more infected plants were observed in completely irrigatedtreatment in comparison with cutoff irrigated treatment. Decreasing the value of the seed yield per plant and hectare affected by irrigation cut-off were 58 and 15%, respectively. Proline contents in irrigation cut-off treatment were about two times more than completely irrigatedtreatment. Khorasan and Kerman ecotypes had higher value in comparison with Esfahan in all studied traits.. Seed yield per hectare for Kerman, Khorasan and Esfahan ecotypes were 525, 306 and 525 kg, respectively. The highest essential oil yield (14.92 kg ha-1) was gained in 1 Mm spermidine for Khorasan ecotype and the lowest (6.87 kg ha-1) was observed in 0 Mm spermidine for Esfahan ecotype. There was no significant difference between foliar application levels in terms of the studied traits such as….
Conclusion: Irrigation cutoff at flowering stage caused a significant increase in seeds per umbel, infected plants and seed yield per plant and hectare Whereas harvest index, essential oil percentage and yield and proline contents were higher in irrigation cutoff treatment compared to completely irrigated treatment. Khorasan and Kerman ecotypes achieved higher potential for cultivation in Kerman climate condition compared to Esfahan ecotype.
Maryam Jabbarzadeh; َAli Tehranifar; Jafar Amiri; Bahram Abedy
Abstract
Introduction: Salinity is one of the most important environmental factors that regulates plant growth and development, and limits plant production. Researchers have shown that some plant growth regulators such as nitric oxide improve the plants resistance to environmental stresses such as heat, cold, ...
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Introduction: Salinity is one of the most important environmental factors that regulates plant growth and development, and limits plant production. Researchers have shown that some plant growth regulators such as nitric oxide improve the plants resistance to environmental stresses such as heat, cold, drought and salinity. Sodium nitroprusside (SNP) commonly has been used as nitric oxide (NO) donor in plants. NO is a diffusible gaseous free radical. Low concentrations of NO inhibit the production of reactive oxygen species and protect plants against ROS damages. The aim of this study was to evaluate the role of SNP as NO donor on salt tolerance of Calendula officinalis and its effects on some morphological, physiological and biochemical characteristics of this plant.
Materials and Methods: In this study, the effects of salinity (0, 25, 50, 75 and 100 mM) and sodium nitroprusside (0.0, 0.25, 0.50 and 0.75 mM) on morphological and physiological characteristics of Calendula officinalis L. were investigated. Total leaf area and number of leaves were determined in the end of the experiment. Electrolyte leakage was used to asses’ membrane permeability. This procedure was based on Lutts et al.,1995. Soluble sugars were extracted and estimated by the method of Irigoyen et al., 1992. Chlorophyll a, b and carotenoid content were calculated from the absorbance of extract at 653, 666 and 470 nm using the formula of Dere et al., 1998. Proline was extracted by the method of Bates et al., 1973. DPPH radical- scavenging activity of sample was performed as described previously of Cleep et al., 2012. The SAS software was used for the analysis of variance (ANOVA), comparisons with P
Farzaneh Olyaei; Bahram Baninasab; Cyrus Ghobadi
Abstract
Introduction: Salinity is a common abiotic stress that seriously affects crop production around the world, particularly in arid and semi-arid regions.The deleterious effects of salinity on plant growth are associated with low osmotic potential of soil solution (water stress), nutritional imbalance, specific ...
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Introduction: Salinity is a common abiotic stress that seriously affects crop production around the world, particularly in arid and semi-arid regions.The deleterious effects of salinity on plant growth are associated with low osmotic potential of soil solution (water stress), nutritional imbalance, specific ion effect (salt stress), or a combination of these factors. Olive is one of the most important fruit crops in Iran and the world. Despite olive has been classified as moderately salt tolerant plant, poor quality of irrigation water in association with salt build-up soils has reduced the yields, especially in arid and semi-arid regions of Iran. The tolerance of the olive to salt is to a great extent depends on the cultivar. Selecting salinity-resistant cultivars is one of the most important strategies used for mitigating salinity effects on olive. Therefore, this study was performed to assess the salt tolerance of four olive cultivars under greenhouse condition.
Materials and Methods: For this purpose, one-year-old rooted cuttings of Iranian olive cultivars (‘Dakal’, ‘Shiraz’, ‘Zard’) and non-Iranian cultivar ‘Amigdal’ were grown in the research greenhouse of Agricultural College, Isfahan University of Technology of Iran. Plants were grown in plastic pots. The pots were 180 mm in diameter and 20 mm in depth with volume of 7 L. The minimum and maximum temperatures during the experiment period were 19 and 35˚C, respectively. After sticking the cuttings, the pots with uniform plants were subjected to the treatment with 0 (control), 100, 150 or 200 mMNaCl. The electrical conductivities of these solutions were 0.003, 10.52, 15.43 and 19.55 dS m-1, respectively. To avoid osmotic shock, the NaCl concentration was gradually increased. The layout was a 4×4 factorial experiment based oncompletely randomized design, with four replications. The experimental measurements were carried out three months after beginning the salt treatments.
Results and Discussion:The results showed that salt stress and cultivar hadsignificant effects on all of vegetative and physiological parameters. Injury rating valueof plants wasfound to increase significantly as the salt concentration was raised. Among the cultivars, the highest injury rating value (2.75) belonged to Amigdal cultivar, while the lowest means (2.00) was related to Dakal cultivar. By increasing the salinity level, stem heightincreasing ratesignificantly decreased. The lowest means (18.17%) belonged to 200 mMNaCl treatment, showing 81.83% decrease compared with control. Among the cultivars, Zard showed the highest means of increase in stem height (71.75%). Leaf area influenced significantly by salinity, sothat the lowest means of leaf area (35.05%) was recorded for200 mMNaCl treatment, showing a 69.91% decrease compared with the control. The highest leaf area belonged to Shiraz cultivar, which had a significant difference with Zard and Amigdal cultivars. Compared with the control, salinity caused 50.83% and 54.36% decreases in shoot fresh and dry weight in 200 mMNaCl, respectively. The highest shoot fresh and dry weightswere recorded forZard cultivar. The lowest shoot fresh and dry weights were observed forAmigdal cultivar.Increment of salinity concentration significantly declined root fresh and dry weight. Among the cultivars, the highest means of root fresh weightbelonged to Amigdal cultivar, whereas the lowest was related to Shiraz cultivar. The highest and lowest root dry weightswere observed forDakal and Amigdal cultivars, respectively.Salinity significantly decreased relative water content.The lowest leaf relative water content (66.04%) was recorded in 200 mMNaCl treatment, showing a 23.43% decrease compared with the control.Zard cultivar showed the highestleafrelative water content. Salinity stress decreased chlorophyll fluorescence in leaves of salt-treated olive plants. At 200 mMNaCl, leaf chlorophyll fluorescence was minimal as compared to control and other salt levels. The highest leaf chlorophyll fluorescence ratio (0.74) was recorded forZard cultivar. However, Amigdal cultivar showed the lowest means for this index (0.60).Salinity significantly decreasedleaf chlorophyll content.The lowest leaf chlorophyll content (69.39%) was recorded in 200 mMNaCl, showing a 66.80% decrease compared with the control.Among the cultivars, Zard showed the highest leaf chlorophyll content (170.33). In the present study, the increase in proline content in the NaCl-treated plants was noted, with the highest level being attained with 200 mMNaCl. The highest proline content (1.03 µmol.g-1 F.W.)was observed in Zard cultivar. Salinity stress increased malondialdehyde content in the leaves of salt-treated plants. The highest malondialdehyde content was obtained from leaves of plants treated with 200 mMNaCl. The highest malondialdehyde content was recorded in Amigdal cultivar.Shirazl cultivar showed the lowest malondialdehyde content. In this study, the correlation betweenvegetative and physiological parameters of olive plants subjected to salt stress was analysed. These correlations suggested that salt injury symptoms was negatively correlated with relative water content, leaf chlorophyll fluorescence and leaf chlorophyll content, but positively correlated with proline content and malondialdehyde content.
Conclusion: In overall, this investigation revealed that salt stress had aninhibitory effect on the vegetative growth of olive plants.The responses of olive cultivars to salt stress suggested that Zard and Shiraz cultivars were more tolerant and ‘Amygdal’ was the most sensitive to changes in the salt levels.
Behrooz Golein; Vali Rabiei; Faezeh Mirabbasi; Reza Fifaei; Mohammad Fazel Halaji Sani
Abstract
Introduction: Citrus (L.) is a large genus that covers several major cultivatedspecies, including Citrussinensis (sweet orange), C.reticulata (tangerine and mandarin), C. limon (lemon), C.grandis (pummelo), and C. paradisi (grapefruit).Citrus is one of the world’s important fruit crops and grown inmost ...
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Introduction: Citrus (L.) is a large genus that covers several major cultivatedspecies, including Citrussinensis (sweet orange), C.reticulata (tangerine and mandarin), C. limon (lemon), C.grandis (pummelo), and C. paradisi (grapefruit).Citrus is one of the world’s important fruit crops and grown inmost areas with suitable climates between latitude 35◦N–35◦S. InIran, citrus industry is of paramount importance. Citrus species have been classified as salt-sensitive crops, although their relative tolerance can be influenced by climate, fertilization, soil type, irrigation method and rootstock. Citrus rootstocks differ in their ability to exclude Cl−and/or Na+from the scion. Many authors have contrasted the relative abilities of rootstocks to restrict movement of salts to the scions. The rootstocks Cleopatra mandarin (C. reshni), Rangpur lime (C. limonia) and Severiniabuxifolia (Poir) Tenore were relatively effective in restricting Cl−transport to scions, whereas the rootstocks Swingle citrumelo and Carrizo citrange were found to be less restrictive. Although the mechanism by which some rootstocks reduce concentrations of ions in the scion is still unknown, it seems to depend on the vigor of the scion and on water requirements. There are a number of reports demonstrating that both scion and rootstock may influence Cl−accumulation in leaves. Several papers reported that accumulation of Na+ in shoots seemed to be more dependent on rootstock–scion combinations. Since, citrus species are different in salt tolerance and use of tolerant rootstocks can decrease salinity damages, sothis study was conducted to identify tolerant genotypes among unknown types from the Kotra Citrus Research Station, Citrus and Sub-Tropical Fruits Research Center (Ramsar).
Materials and Methods: The experiment was –arrangedin afactorial, based on completely randomized design in three replications with two plantsin each experimental unit in Iran Citrus Research Institute.Treatment included 10 citrus natural genotypes along with two varieties of Cleopatra mandarin (tolerant plant) and Swinglecitrumelo (sensitive plant) with six-month old and four salinity levels of sodium chloride: 0(control), 2, 4 and 6 dsm-1, for 16 weeks in the greenhouse condition. Effect of salinity on fresh and dry weight of shoot and root, relative water content (using upper leaves), stomatal density (with counting of stomata using microscope), concentration ofCl (with titration method of silver nitrate) and Na (by flame photometry) in roots and leaves, content of total chlorophyll (using acetone 80%), proline (spectrophotometry at wavelength of 520 nm), lipid peroxidation (spectrophotometry at wavelength of 532 nm) and activity of peroxidase enzyme (spectrophotometry at wavelength of 470 nm)were investigated. Data analysis was done by SAS 9.1 software.
Results and Discussion: The results indicated that, the interaction of genotypes and salinity levels hadnot significant difference in relative water content, stomatal density and Na+concentration - in roots but, other traits except total chlorophyll content which was significant at 5% level, were significant at 1% level. Shoot fresh and dry weight of genotypes No. 4 and 6 were significantly (P
Sakineh Hasanzadeh; Fariborz Habibi; Mohammad Esmaeil Amiri
Abstract
Introduction: Pomegranate (Punica granatum L.) belongs to the Punicaceae family and grows in subtropical and Mediterranean climates. Nowadays the widespread usage of inorganic fertilizers has increased and so people concern about their health. The use of organic fertilizer instead of inorganic fertilizers ...
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Introduction: Pomegranate (Punica granatum L.) belongs to the Punicaceae family and grows in subtropical and Mediterranean climates. Nowadays the widespread usage of inorganic fertilizers has increased and so people concern about their health. The use of organic fertilizer instead of inorganic fertilizers is one of the methods of preserving health. Pomegranate is one of the most important products of Iran. This fruit plant is cultivated in some regions in arid and semi-arid areas. Due to the long growing season of pomegranate, droughtstress is one of the main limiting factors in the development of pomegranate orchards in Iran. Utilization of amino acids can help to increase efficiency and improve the quality of the fruit under environmental stress. Thus, this study aims to findany possibility to increase the production and quality of the fruit during the drought. The goalof this study was to study the effect of organic Aminol-Forte fertilizer on physiological and biochemical responses of pomegranate cv. Naderi under drought stress conditions.
Materials and Methods: This research was carried out in AbShirin field located on the old road 40 km from Qom-Kashan during 2011. Asplit plot experiment based on randomized complete block design was conducted with two factors, irrigation treatment in three levels (100% required water, 75% required water and 50% required water) and Aminol-Forte fertilizer treatment in four levels (0, 2, 3 and 4 ml/l). Spraying was conducted in four stages (pre-anthesis, after fruit set, fruit growth andtwo weeks per-harvest). In the end of the experiment, chlorophyll index, soluble sugars, insoluble sugars, proline, canopy degree and stomatal conductance were measured. Statistical analysis was performed using SPSS 17 program. Means were separated according to the Duncan’s multiple range test (DMRT) at 0.01 level of probability.
Results and Discussion: Analysis of variance of Aminol-forte fertilizer spraying on physiological and biochemical responses of pomegranate cv. Naderi under drought stress conditions showed that between irrigation treatment for chlorophyll index, proline and stomatal conductance were significant at 1% level of probability, and at 5% level of probability soluble sugarand insoluble sugar and canopy degree were significant. Fertilizer treatment at 1% level of probability was significant for proline and at 5% level of probability was significant for soluble sugars. Interaction was significant for soluble sugars, proline and canopy degree. Means showed that by increasing fertilizer level, soluble sugars content, proline and stomatal conductance significantly increased insoluble sugars and chlorophyll index decreased insignificantly. By decreasing irrigation levels, chlorophyll index, soluble sugars and proline significantly increased, meanwhile insoluble sugars and stomatal conductance significantly decreased. The highest chlorophyll index (65.44 SPAD) and the lowest chlorophyll index (56.48 SPAD) were obtained in 75% required water with 2 ml/l of fertilizer level and 100% required water with 3 ml/l of fertilizer level, respectively. The highest soluble sugars (14.94 mg/g) and the lowest soluble sugars (11.64 mg/l) were obtained in 50% required water with 0 ml/l of fertilizer level and 100% required water 2 ml/l of fertilizer level, respectively. The highest insoluble sugars (9.99 mg/g) and the lowest insoluble sugars (6.82 mg/l) were measured in 100% required water with 3 ml/l of fertilizer level and 50% required water with 2 ml/l of fertilizer level, respectively. The highest proline content (2.51μmol/l) and the lowest proline content (1.05μmol/l) were obtained in 50% required water with 4 ml/l of fertilizer level and 100% required water with 0 ml/l of fertilizer level, respectively. The highest canopy degree (-7.31˚c) and the lowest canopy degree (-9.38˚c) were measured in 50% required water with 4 ml/l of fertilizer level and 100% required water with 4 ml/l of fertilizer level, respectively. The highest stomatal conductance (38.23 mmol/m2/s) and the lowest stomatal conductance (9.7 mmol/m2/s) were obtained in 50% required water with 2 ml/l of fertilizer level and 100% required water with 3 ml/l of fertilizer level, respectively.
Conclusion: By increasing the level of Aminol-Forte fertilizer from 0 to 4 ml/l, soluble sugars content, proline and stomatal conductance significantly increased meanwhile insoluble sugars and the chlorophyll index decreased. Drought stress increased soluble sugars content, chlorophyll index, canopy degree and proline but, insoluble sugars and stomatal conductance decreased. According obtained results, it can be said, spraying of Aminol-Forte fertilizer containing amino acid could significantly reduce the negative effects of drought stress. In this study, the best results in terms of stress and no stress were obtained in 3 and 4 ml/l of Aminol-Forte fertilizer.
Mehri Mashayekhi; Mohammad Esmaeil Amiri; Fariborz Habibi
Abstract
Introduction: Salinity is the most significant abiotic factor limiting crop productivity and several physiological responses, including modification of ion balance, water status, mineral nutrition, stomatal behavior, photosynthetic efficiency and so on. The GF677 (Prunuspersica×Prunusamygdalus) is widelyusedas ...
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Introduction: Salinity is the most significant abiotic factor limiting crop productivity and several physiological responses, including modification of ion balance, water status, mineral nutrition, stomatal behavior, photosynthetic efficiency and so on. The GF677 (Prunuspersica×Prunusamygdalus) is widelyusedas rootstock for peach and almond. It is mainly used as a rootstock because of its resistance to drought, calcic soil and Fe deficiency. Nowadays, using tissue culture techniques is very popular for the selection of plant resistant to abiotic stress (in vitro salinity); because in vitro conditions are more controllable than in vivo conditions and the large number of genotypes can be evaluated in a limited space. For example, in the field, plants are exposed to variable biological and climatic conditions which result in some interaction effects. In other words, the nutrition and climatic effects are easily controllable in the in vitro conditions all over the year. The objective of this study is to identify biochemical markers of salinity stress of GF677 rootstock under in vitro conditions.
Materials and Methods: Plantlets of GF677 rootstock were subcultured into the Murashige and Skoog (MS) proliferation medium containing1 mg/l BA (6-Benzyladenine)and 0.1 mg/l NAA (naphthaline acetic acid) with different concentrations (0, 40, 80 and 120 mM) of sodium chloride (NaCl) with four replicates. Cultures were transferred to the growth chamber with temperature of 25±2°C, relative humidity of 70%, under a 16/8 h (day/night) photoperiod. Data were collected at the end of the experiment (6th weeks). Antioxidant enzymes activity (catalase and peroxidase),total protein content, proline content, soluble sugars, and Na and Cl were measured. The experiments were set up in a completely randomized design (CRD) with four replicates (a vessel in each replicate) and statistical analysis was performed using MSTAT-C program. Means were separated according to the Duncan’s multiple range test (DNMRT) at 0.05 level of probability.
Results and Discussion: After six weeks, the results showed that by increasing salinity levelsin the culture medium, antioxidant enzymes activity (catalase and peroxidase),total protein content, proline content and soluble sugars increased significantly. The antioxidant enzyme activities (catalase and peroxidase) were increased significantly in the GF677 rootstock by increasing salinity levels. Catalase activity increased with increasing salinity levels, such that the maximum value (0.61 [abs/min /mg protein (f.m)]) was observed in 80 mM sodium chloride treatment. The lowest catalase activity (0.11 mg [abs/min /mg protein (f.m)]) was observed in 120 mM. The highest of peroxidase enzyme activity (0.109 and 0.105 [abs/min /mg protein (f.m)]), was obtained in 80 and 40 mM, respectively. Also, by increasing the salinity level, total protein content increased significantly in GF677 plantlets. The highest total protein was observed in 80 mM sodium chloride. By increasing salinity levels, proline content increased compared to the control at the GF677 rootstock, but no significant difference was observed between salinity levels. The highest accumulation of proline was obtained in 80 and 120 mM, respectively, while the lowest proline was obtained in control. By increasing salinity levels, soluble sugars increased in GF677 rootstock. The highest accumulation of soluble sugars was obtained in 80 mM. By increasing salinity levels in the cultural medium, the uptakeof sodium (Na+) and chlorine (Cl-) significantly increased in GF677 rootstocks over the six-week culture period. The highest uptake of Na and Cl ions in plant tissue was observed in 4th week. The results showed that with increasing salinity levels (80 to 120 mM), leaf chlorophyll index (SPAD unit) decreased in GF677 rootstock. The lowest chlorophyll index was observed in 120 mM treatment, while the highest leaf chlorophyll index was obtained in the control treatment.
Conclusion: According to the results and analysis of biochemical and enzymatic responses,it can be concluded that GF677 is a concentration tolerant to salinity up to 120 mM. The highest amount of biochemical responses and enzymatic activity was observed at 80 mM, where the continued growth of the plant was in terms of salinity. The rootstock was due to antioxidant defense mechanisms such as antioxidant systems, osmotic adjustment by proline and soluble sugars and increasing protein synthesis can sustain growth even under salinity conditions, as a tolerant rootstock was used for peach and almond cultivars.
Amir Sadeghi; Nematollah Etemadi; Mahboobe Shams; Fateme Nyazmand
Abstract
In this study, the effect of drought stress on morphological and physiological characteristics of wheatgrass and tall fescue was investigated in a factorial-split plot in time arrangement based on a completely randomized design with three replications. After turf establishment, half pots were exposed ...
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In this study, the effect of drought stress on morphological and physiological characteristics of wheatgrass and tall fescue was investigated in a factorial-split plot in time arrangement based on a completely randomized design with three replications. After turf establishment, half pots were exposed to drought stress and the half other were completely irrigated. Based on the results tall fescue had higher color and lower percent leaf firing during first 10 days of drought stress, but after this period, the percent leaf firing in tall fescue increased, so that it had higher percent leaf firing and lower color than wheatgrass in the end of experiment. The results showed that under drought stress conditions was not observed the significant difference between two species in leaf relative water content. In wheatgrass, proline content of stressed plants was equal to control plants during first 10 days of drought stress but with prolonged stress treatment, the proline content increased significantly. Despite wheatgrass which had moderate rate for closed stomata percentage during stress period, tall fescue showed a great increased in this index and reached to 89.52% at the end of 20th day. Also in drought stress, the stomata density increased and stomata diameter decreased significantly. Therefore, based on the results in long drought stress, wheatgrass had higher drought resistance than tall fescue.
Maryam Haghighi; Mohsen Kafi
Abstract
Information of heavy metal toxicity about physiological aspect of lettuce is limited. Therefore an experiment was conducted in CRD designed with 7 replications on lettuce (Lactuca sativa L.). Treatments were cadmium in 3 concentration (0, 2 and 4 mg/L) added to Hoagland solution. Results were shown that ...
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Information of heavy metal toxicity about physiological aspect of lettuce is limited. Therefore an experiment was conducted in CRD designed with 7 replications on lettuce (Lactuca sativa L.). Treatments were cadmium in 3 concentration (0, 2 and 4 mg/L) added to Hoagland solution. Results were shown that increasing in cadmium of nutrient solution caused increasing in SOD, POD antioxidant and proline contents of leaf tissues, in addition, cadmium decreased the amount of fresh weight and organic acid. Applying 2 and 4 mg/L cadmium in nutrient solution produced POD, SOD and Proline around 8 and 53%, 55 and 106%, 39 and 119% in 2 and 4 mg/L cadmium, respectively. Whereas in the same concentrations of cadmium protein decreased 25 and 5 %, respectively. Under cadmium stress, toxic effects decline photosynthesis more than chlorophyll content.
Fatemeh Abri; Mahmood Ghasemnejad; Reza Hassan Sajedi; Davoud Bakhshi; Mohammad Ali Shiri
Abstract
In this study, effect of different concentration of ascorbic acid (AsA, 0, 2, 4 and 6 mM) on delaying senescence in cut rose flowers cv. Royall Class was investigated based on factorial design. The results showed that the greatest delay in senescence was obtained with 4 mM AsA as compared to control ...
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In this study, effect of different concentration of ascorbic acid (AsA, 0, 2, 4 and 6 mM) on delaying senescence in cut rose flowers cv. Royall Class was investigated based on factorial design. The results showed that the greatest delay in senescence was obtained with 4 mM AsA as compared to control (distilled water). Therefore, fresh weight and diameter of flowers treated with 4 mM AsA was more than others treatments. Biochemical attributes such as protein, proline, anthocyanin content and lipid per oxidation levels were determined only in DW and 4 mM AsA. Application of 4 mM AsA treatments was shown to retard degradation of protein over 8 days vase life. Proline content in AsA treated flowers was slightly lower than DW flowers but no significant differences were found in treated flowers with AsA. Anthocyanin content declined gradually with onset of senescence, while AsA treatments suppressed decreasing its content. Therefore, treatment with 4 mM AsA suppressed malondialdehyde accumulation and delayed flowers senescence.
Maryam Sadat Araghi Shahri; Mehrdad Lahouti; Fereshte Ghasemzadeh; Hamid Ejtehadi
Abstract
Antimony is a toxic heavy metal for plants, animals and human being. Considering its effects on plants growth, different concentrations on watermelon growth and development were studied. The experiment was established on a factorial experiment based on a completely randomized design with 3 replications. ...
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Antimony is a toxic heavy metal for plants, animals and human being. Considering its effects on plants growth, different concentrations on watermelon growth and development were studied. The experiment was established on a factorial experiment based on a completely randomized design with 3 replications. The seedlings were grown hydroponically in nutrient solution containing Sb-EDTA (0, 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6 and 8 mg/L). Samples were harvested after four weeks to determine biochemical and morphological parameters. With increasing Sb concentration in culture medium, resulted in significantly decreased chlorophyll content and some other growth parameters in treated plants (p
Mehri Yusefi; Seyyed Jalal Tabatabaie; Jafar Hajilou; Naser Mahna
Abstract
Salinity affects the yield and quality of fruits crops as result of modifying water and nutrient uptake. In split root system, it should be possible to reduce the deleterious effect of salinity on the plant growth. Therefore, an experiment was conducted on strawberry with different concentration of NaCl ...
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Salinity affects the yield and quality of fruits crops as result of modifying water and nutrient uptake. In split root system, it should be possible to reduce the deleterious effect of salinity on the plant growth. Therefore, an experiment was conducted on strawberry with different concentration of NaCl (0, 30, 60 and 90 mM) in a completely randomized blocks design in studding hydroponic greenhouse. The roots were divided into two portions and either even or uneven salinity was applied to the root portions. The treatments consist of 0:0, 0:30, 0:60, 0:90, 30:30, 60:60 and 90:90 with three replications. In general, the increased salinity reduced photosynthesis rate but in uneven salinity the photosynthesis rate was increased. Proline concentration was reduced in 0:0 treatments but increased in 0:30 and 30:30 treatments. Ca, N, P and K concentrations were reduced by increasing salinity, but were increase in uneven salinity. The highest concentrations of Cl and Na were observed in 60:60 and 90:90 salinity treatments. Na and Cl concentrations were reduced in uneven salinity in the root zone so that in 0:30 treatments, the concentration of Na were 20% lower than that in 30:30 treatments. Based on the results of this study the application of uneven salinity in a concentration of 30 mM could be recommended for growing strawberry in salinity stress conditions.
Morteza Goldani; Yahya Selahvarzi; Jafar Nabati; Morteza Alirezaie Noghondar
Abstract
Salinity is one of the environmental stresses that have limited influence on the crop growth. Oxidative process is a secondary stress due to salinity. Oregano is enumerated as one of the most important of medicinal plant that its production and development is possible in Iran. In order to study the effect ...
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Salinity is one of the environmental stresses that have limited influence on the crop growth. Oxidative process is a secondary stress due to salinity. Oregano is enumerated as one of the most important of medicinal plant that its production and development is possible in Iran. In order to study the effect of exogenous application of hydrogen peroxide on salt tolerance in oregano (Origanum majorana L.) an experiment was conducted in greenhouse conditions. This study was designed as factorial based on completely randomized design with 3 replications. Different concentration of hydrogen peroxide (0, 2.5 and 5 mM) and four levels of NaCl (0, 50, 10 and 150 mM) were treated in this study. Results showed that foliar application of hydrogen peroxide can improve shoot and root dry weight and alleviate adverse effects of salinity. In the other hand, high concentration of hydrogen peroxide (5mM) increased total chlorophyll and caroteoid content about 46.6 and 100.6 percent comparing to control plant, respectively. Salt stress had no significant effect on cellular hydrogen peroxide, but it increased free proline and reduced K:Na ratio. While hydrogen peroxide content, free proline and K:Na ratio were increased 104.6, 320.7 and 77.8 percent by high level of hydrogen peroxide, respectively. The final result showed that foliar application of hydrogen peroxide decreased salt stress.
