Journal of Plant Process and Function

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Abstract: Enhanced leaf proline, soluble sugar and soluble protein contents with sever salinity stress can improve stomatal conductance and Relative water content. This can inhibit dry matter depletion due to salinity stress, so can be used for screening of safflower cultivars under salinity stress. To evaluate the changes in leaf proline, soluble sugars, glycinebetaine and protein content of six spring safflower under salinity stress, a pot experiment was conducted as factorial base on completely randomized design with three replications in summer 2011 in Yasouj University. The first factor included of four salinity levels as zero, 75, 150 and 225 mM. Second factor included of six safflower cultivars, as Local Isfahan, Spinned Sina, Isfahan 14, Goldasht, Padideh and Sina 411. Traits such as leaf Proline, glycinebetaine, soluble sugars and soluble protein content and leaf relative water content were measured. Interaction of salinity and cultivar was significant for all measured traits. Salinity stress significantly increased leaf proline and soluble sugar content. Relative water content decreased significantly by salinity, so that maximum of it (91.03%) was seen in Padide at control. Sina 411 due to having more leaf soluble sugar and RWC at 225 mM salinity level and Goldasht due to having more proline and glycinebetaine content was more tolerance cultivars than the others, and Esfahan14 that had the least soluble sugar, Relative water content and glycinebetaine content introduced as less tolerant cultivar.

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Rozita Kabiri, Fatemeh Nasibi*, Hassan Farahbakhsh 1Department of Agronomy, Faculty of Agriculture, 2Department of Biology, Faculty of Sciences and 3Horticultural Research Institute, Shahid Bahonar University of Kerman (Received: 01 October 2012 Accepted: 17 March 2013) Abstract: Drought stress is one of the main stresses that inhibits the growth of plants due to mainly disturbance of the balance between production of reactive oxygen species and antioxidant defense and thereby causing oxidative stress. Evaluation of medicinal plants tolerance to drought stress in order to plant them in dry region is very important. In this research, oxidative parameters of drought stress induced by different concentration of polyethylene glycol solutions in Nigella plant were investigated. To control experimental conditions including the inhibitory effects of the other factors such as soil nutrition the hydroponic medium was used. In this study, drought stress significantly increased the H2O2 content, lipid peroxidation and lipoxygenase activity which were showed the oxidative stress induced by drought in Nigella plants. Study of the defense mechanisms, through the measurement of the antioxidant enzymes activities indicated that drought stress increased the activity of ascorbate peroxidase, catalase and guaiacol peroxidase. However in this research, we observed that the increment in drought level had no significant effects on catalase and guaiacol peroxidase activity. It seemed that in this investigation the increment of proline might be related to both osmotic and antioxidant characteristic of this compound. Increase of lipid peroxidation and H2O2 content in drought stress showed that the scavenging and quenching of ROS were out of the plant ability and the induction of plant defense mechanism against oxidative damages was not effective. Therefore, the application of exogenous protect compound could increase the antioxidant capacity of plant against stress condition. *Corresponding author:

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Yahya Emam1*, Hedayatallah Karimzadeh Soureshjani1, Saeed Moori and Kobra Maghsoudi1 1Department of agronomy and plant breeding, College of Agricultural, Shiraz University (Received: 3 September 2012 Accepted: 4 May 2013) Abstract: In order to evaluate some biochemical responses of bread wheat (Shiraz cultivar) and durum wheat (Yavarous cultivar) to late season water stress and different auxin and cytokinin levels, a field experiment was carried out in research farm of the collage of Agriculture, Shiraz University during 2010-2011 growing season using a split split factorial as randomized complete block design with three replications. Irrigation regime (normal and cutting off water at anthesis), wheat cultivars (Shiraz and Yavarous) and factorial combination of auxin (0, 20 and 40 mg/L) and cytokinin (0, 50 and 70 Mm) levels were considered as main, sub and sub sub plats, respectively. The results showed that flag leaf proline and catalase content were increased linearly upon cutting off irrigation at anthesis while, proline and catalase content did not show any significant changes after anthesis under normal irrigation conditions. Moreover, proline content in Yavarous cultivar was found to be significantly greater than Shiraz cultivar. Among cytokinin concentrations, the highest catalase activity was obtained from control treatment. As cytokinin concentrations were increased, catalase activity was decreased under well watered conditions. Peroxidase activity was increased under irrigation cut off conditions, and was enhanced with time lapse from anthesis. Chlorophyll a, b, carotenoid and total of foliage leaf were greater under cut off irrigation conditions. Deep understanding of biochemical responses of wheat cultivars to late season drought stress and its interaction with plant growth regulator needs further complimentary research. yaemam@gmail.com

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In order to study the effects of GA3 on growth and the biochemical compositions of jujube (Ziziphus spina-christi) leaf, this experiment was conducted in 2011-2012, in department of horticultural science of faculty of agriculture Hormozgan University, Bandar abbas and nursery of Major Natural Recourses Office of Hormozgan province, as a factorial basis on completely randomized design with three replications. Experimental factors were 5 salinity levels (0, 1600, 3200 and 12800 ppm NaCl solutions) and 3 different concentrations of GA3 (0, 100 and 200 mg l-1). Seven weeks after GA3 application, leaf number and area, plant total dry weight, leaf Na+ and K+ concentrations, K+/Na+ and proline content were measured. Results indicated that with increasing NaCl concentrations leaf proline and Na+ were increased and other traits under study were decreased, significantly. Foliar application of GA3 alleviated the negative effects of salinity, so that under salinity conditions with foliar spray of GA3 (200 mg l-1) leaf number and area, total dry weight per plant, leaf K+ concentration and proline content were increased. GA3 reduced Na+ and increased K+ in the leaves which resulted in an increase in leaf K+/Na+. Results of this study revealed that foliar application of GA3 might increase jujube plants adoption to saline conditions via either reduction in Na+ absorption or by accumulation of K+ and proline in leaves.

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One of the negative effects of water stress on growth and crop production is micronutrient uptake reduction by plant root. Therefore, to evaluate the effect of foliar application of Fe and Zn on some physiological and morphological characteristics of red bean (Akhtar cultivar) under drought stress this experiment was designed as a split plot in a completely randomized block design with three replications. Irrigation as the main plot at three level: Irrigation after 50, 75 and 100 mm evaporation from pan evaporation, and foliar application of micronutrients as the sub-plot at four level: foliar application with water (control), ferrous sulfate, zinc sulfate and a mixture of ferrous sulfate and zinc (each at a concentration 3/1000) was used. The results showed that delay in irrigation decreased leaf relative water content, chlorophyll content, plant height, number of lateral branches and seed yield and increased electrolyte leakage, leaf prolin and soluble sugar content in compared to control treatment. The effect of foliar application treatments was significant on all traits except leaf soluble sugars and plant height. The foliar application of Fe and Zn increased leaf relative water content, chlorophyll content, number of lateral branches and grain yield, and decreased electrolyte leakage and leaf prolin significantly. According to the results the foliar application of Fe and Zn improved physiological characteristics and stress tolerance in plants. Therefore, the plants were delayed in encountered with water stress condition, and produce a better performance.

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Because of water and soil salinity, there are many problems for turfgrass in Iran. use of salt tolerant native plants is one of the appropriate way for solving these problems. This study was undertaken to evaluate effect of four levels of salinity (less than2, 4, 8 and 16 ds/m) on morphological and physiological characteristics in naitive grass, Wheatgrass (Agropyron desertorum). The experiment was performed based on randomized complete block design with three replications. The results showed that salinity stress decreased turfgrass qualiy (TQ), fresh and dry weight of shoots and roots, relative water content (RWC) and root and shoot potassium contents. Also, salinity stress increased shoot and root sodium contents, electrolyte leakage (EL), proline contents and activity of enzymes. According to reduction in TQ and RWC and increase in EL under salinity stress, it seems that increasing in proline contents and enzymes activities could not be able to reduce the damage caused by stress. All of the measured parameters in this study showed the significant differences with control plant in 4 ds/m salinity level. The results showed the wheatgrass is salt-sensitive and salt tolerance it was less than 4 (ds/m).

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This study was performed in order to evaluate the effects of supplementary irrigation and application of Zn and K fertilizers on physiological characteristics of chickpea. The experiment was conducted in a split plot-factorial using randomized complete blocks design with three replications at campus of agriculture and natural resources, Razi University, Kermanshah, Iran. Supplementary irrigation in two levels (W1= non irrigation and W2= supplementary irrigation at podding stage) was considered as main-plot on the other hand, combination treatments of Zn fertilizer in four levels (Zn1=0, Zn2=20, Zn3=40 and Zn4=60kg/ha) and K fertilizer in three levels (K1=0, K2=50 and K3=100kg/ha) were considered as sub-plots. The results showed that the effects of irrigation on all studied physiological characteristics were significant excluding chlorophyll-a and RWL. Likewise, the effect of Zn fertilizer on all parameters was significant. Moreover, the effect of K fertilizer on all parameters was significant excluding chlorophyll SPAD. Based on the results, supplementary irrigation increased the chlorophyll-a, chlorophyll-b, chlorophyll-ab and relative water content (RWC). Under drought stress condition, proline content and storage protein were more than supplementary irrigation treatment. In the same way, application of K fertilizer improved all parameters excluding RWC. Application of 40kg Zn fertilizer improved all parameters in chickpea. In irrigation condition and already application of Zn and K fertilizers as much as optimum amount plant had a good physiological status and produced highest yield, too.

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Salinity is considered as one of the main limiting factors for growth and production of several agricultural crops all over the world. Also, salinity influences the growth and also synthesis of secondary metabolites of medicinal plants. Salvia viridis and Salvia spinosa are two aromatic species which belong to Salvia genus from Lamiaceae family. As the mechanisms of salt stress tolerance and also the effect of salinity on growth and production of secondary metabolites in these two salvia species have not been studied yet, the effects of salt stress on growth parameters and the essential oil composition in these plants were analyzed. Seedlings of two mentioned species, two weeks after germination and growth, were grown at different levels of NaCl including: 0 (control), 20, 40, 60 and 80 mM NaCl at Hogland medium in a hydroponic system. After four weeks, later, the growth parameters such as: shoot and root dry weight, Na+ and K+ concentrations, the amount of proline and soluble sugars, were measured. Also, the essential oil composition was compared between control and salt stress in S. viridis. Results showed that, by increasing of salt stress levels, shoot and root dry weight of both species were decreased. Salt stress resulted in increasing of soluble sugars and proline concentrations in aerial parts of both species. However, this increase in S. spinosa was a little higher than other species. K+ content was also decreased by salt stress in both species although in S. spinosa this decrease was less than S. viridis. Salt stress resulted in increasing of some essential oil compounds such as: -pinene, -3-carene and linalool in S. viridis in compared to the control plants. It could be concluded that less sensitivity of S. spinosa to salt stress can be attributed to more accumulation of proline and soluble sugars and inhibition of K+ decreasing under salt stress in this species.

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Nitrogen has an important role for supplying carbon skeletons which needs for producing compatible solutes and stress tolerance enzymes. Water deficit affects nitrogen fixation in legums. So we studied the effect of various nitrogen sources on physiological, and biochemical features of bean under water stress. This experiment was conducted as factorial based on completely randomized design with three replications in the greenhouse of university of Mohaghegh Ardabili in 2012. The treatments irrigation included three levels (30, 55, and 80% of field capacity) and nitrogen sources (control, N source as ammonium, nitrate, and nitrate + ammonium). In this experiment lysine and methionine amino acids, catalase and polyphenol oxidase enzymes activity, soluble sugars, proline and proteins content measured in 3, 5 and 7 days after the stress induction. Water stress increased leaf proline and soluble sugars content. Using of nitrate and nitrate + ammonium caused the highest proline and total soluble sugars content, while enhancing stress intensity decreased protein content. Nitrate showed remarkable impact on protein content under water stress conditions. The highest lysine produced by severe stress, whereas methionine decreased by enhancing stress. Supplying mineral nitrogen significantly affected lysine content, compared to the control and increased and nitrate was the most effective nitrogen source for increasing methionine. Catalase and polyphenol oxidase activities were elevated under stress conditions, compared to the non-stress ones. Combined application of ammonium and nitrate showed the highest activities of these enzymes.

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Plants exposed to air pollution show returnable and unreturnable biochemical and physiological alterations. So biochemical parameters can provide valuable information about physiological condition of plants that are subjected to air pollution. This study was performed to determine the effects of air pollutants on the amount of proline, protein, calcium and phosphorus in Medicago sativa and Phaseolus vulgaris leaf and root. We also investigated M. sativa and Ph. vulgaris resistance to the air pollution in Arak Oil Refinery area. The plant samples were collected from polluted and non polluted area and the amount of proline, protein, calcium and phosphorus in leaf and root of plants were determined. The results showed that air pollution led to a significant increase of proline in leaf and roots of both M.sativa and Ph. Vulgaris. Air pollution also led to a significant increase of protein concentration in M. sativa (leaf and root), but a significant decrease of protein concentration in Ph. vulgaris leaf and root. Concentration of calcium in M. sativa leaf and root under air pollution implied a significant increase. However air pollution caused a significant decrease of calcium in Ph. vulgaris root and no significant alteration of calcium rate in Ph.vulgaris root. Air pollution led to a significant increase of phosphorus rate in M. sativa root, but no significant alterations in M. sativa leaf, instead a significant increase of phosphorus rate in Ph. vulgaris leaf and root. In this study, increasing of protein and calcium in M. sativa plant was indicative of its resistance to the air pollution, and changes in biochemical parameters in Ph. vulgaris implied its sensitivity to the air pollution.

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Heavy metals are the most important pollutants in the environment. The productiion of toxic metals by human activities has lead to the contamination of soil. The presence of these metals in the soil and their accumulation in plants grown on these soils will have adverse effects on humans and animals. One approach to reduce the accumulation of heavy metals in plants is using of plant hormones. This study was designed to investigate the effects of methyl jasmonate on accumulation of lead on radish (Raphanus sativus L.) in hydroponic conditions. Lead sulfate with four different concentrations (0,250,500 and 750 mg/ L) and methyl jasmonate with three concentrations (0, 0.01 and 0.1 mM) were used. The experiment was conducted as factorial in a completely randomized design with three replications. The contents of chlorophyll a and b, proline and Pb accumulation in shoots and roots of plants were measured. The results showed that the lead reduced chlorophyll content and this reduction with 0.01 mM methyl jasmonate treatment was compensated. In addition, lead and methyl jasmonate significantly increased proline content. As a result, it can be concluded that radish is probably prone to accumulate heavy metals like lead in the edible parts and this toxicity can be reduced by using appropriate concentrations of methyl jasmonate.

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To investigate the effects of Cd and Cd-Sodium nitroproside (SNP) on growth and physiological parameters of Melia azedarach, this experiment was done in a completely randomized design in three replicates and arranged as factorial. Results showed the amounts of Cd and proline in the root of the plant significantly increased as Cd concentration in soil increased. Length and weight of roots decreased with increasing Cd in soil. Increasing cd concentration in soil did not affect the amounts of soluble sugar, relative water content and MDA. SNP compared to treatments without SNP increased the amount of fresh weight of root significantly. Since SNP did not affect almost none of growth the parameters in Melia azedarach, it was concluded that this compound did not play an important role in protection of the plant against heavy metal.

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Half-sib mating is an appropriate approach to estimate additive variance component of quantitative traits. This research was conducted to estimate genetic parameters of physiological traits and their response to drought stress in Dactylis glomerata. Twenty five half sib families derived from poly cross of 25 parental genotypes were evaluated under two moisture environments (normal and drought conditions) according to a randomized complete block design in the research farm of Isfahan University of Technology. Results indicated that drought stress significantly affected forage yield. Significant difference was observed among the families for all of the studied traits except for ratio of total chlorophyll to carotenoid and relative water content. Drought stress increased traits with respect to chlorophyll a/b and prolin in stress condition compared with normal condition while other traits decreased in drought condition. Genotypic coefficient of variation varied between 4.5 to 31.08 % under non-stress condition and from 5.7 to 66.27% in drought condition indicating high genetic variation in this germplasm. The highest narrow sense heritability was related to total chlorophyll (78%) and the lowest one was related to relative water content (29%) in non stress condition. Also, highest and lowest narrow sense heritability were related to proline content (66%) and relative water content (17%) respectively. Regarding high heritability of proline content and chlorophyll b under drought stress, indirect selection through these traits may facilitate breeding for drought tolerance.

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In order to study the effect of chitosan on growth and some biochemical characteristics of chickpea under salinity stress condition a greenhouse experiment was conducted in Vali-e-Asr University of Rafsanjan in 1392, as factorial arrangement in completely randomized design with three replications. Experimental factors included salinity (0, 4, 6 and 8 dS/m) and level of chitosan (0, 0.1, 0.2%, all dissolved in 1% acetic acid) along with an additional treatment of distilled water. Results indicated that with increasing salinity malondialdehyde content (0.834 mM g-1), proline (0.254 mg.g-1 FW), total carbohydrate (10.48 mg.g-1 FW), Na+ concentration of shoot (1.87%), Na+ concentration of root (2.05%) were increased while other traits under study were decreased. Chitosan treatment increased shoot height, shoot dry weight and relative water content and decreased malondialdehyde content. Under salinity conditions, chitosan treatment root height, root dry weight, proline and total carbohydrate were increased. Also, chitosan increased K+ concentration and decreased Na+ concentration of shoot under both unstressed and stressed condition. In plants treated with chitosan, K+ concentration of root increased compared with control plants, but the Na+ concentration of root decreased by 7.14 %. The results of the study indicate that priming the chickpea seeds with chitosan reduce the harmful effects of salinity via either reduction in Na+ absorption or by accumulation of proline, total carbohydrate and K+.

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Regarding the differences between shoot and root optimum growth temperature and the impress of temperature on root function specially nutrient absorption this study was aimed to investigate the effect of low root temperature with three nitrogen levels in lettuce. The experiment was conducted in factorial completely randomized trial design with five replication. Treatments were used including three nitrogen levels (100, 75 and 50) % Johnson nutrient solution and two temperature levels (15ºC: stress condition, 25ºC: optimum condition). The experiment was performed in greenhouse of Isfahan University of Technology. Results indicated that by decreasing nitrogen and temperature levels prolin and root exudate phenol in T2×N3 treatment were 98 and 8 % higher than control treatments respectively. Furthermore in photosynthesis rate and stomata conductivity with 80 and 56 % reduction from control treatment the lowest amount of them observed. Also photosynthetic water efficiency and chlorophyll index were 69 and 70 % more than control treatment respectively. Shoot and root fresh weight were 50 % more than other treatments. Under low temperature stress photosynthesis rate, evaporation, stomata conductivity and the amount of phenolic compounds and proline mostly impressed. Based on present results in order to obtain lettuce greatest yield we should satisfied its temperature and nutritional needs but plants will be resistance under stress condition by releasing prolin and phenolic compounds.

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In order to evaluate the effect of seed priming on some effective physiological parameters on seed germination of pea (Pisum sativum L.) under chilling stress, a factorial experiment was conducted in completely randomized design with four replications. Treatments were consisted of priming treatments (hydropriming, halopriming, osmopriming and no priming) and temperature (3, 6, 9, 12 and 15 ˚c). Results showed that chilling stress caused a linearly decline of germination rate. The maximum germination rate achieved with hydropriming treatment. Also, hydropriming treatment prevented the reduction of germination percentage at 3˚C with no significant difference with halopriming treatment. The maximum vigor index was observed for halopriming. Reduction of temperature resulted in proline and activity of catalase and guaiacol peroxidase enzymes increasing in all priming treatments. Polyethyleneglycol not only had no effect on seeds germination, but also reduced germination parameters of pea in some temperatures. In conclusion, hydropriming and halopriming treatments are suitable for physiological parameters, germination rate and percentage improvement of pea seeds under chilling stress conditions that they can provide establishment and better growth of this plant under cold stress. This method could be appropriate for increasing the rotational potential of this plant as green manure in cold and mild regions of the country.

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Tuberosa (Polianthes tuberosa L.) is one of the most important cut flowers in Iran and word wide which the increment of postharvest life of this flower is very important. In this research proline as an antioxidant compound was used in 0(control), 1 and 10 micro molar concentrations and the effects of this compound on some morphological and physiological characteristics and vase life of tuberosa cut flower were investigated. The experiments were performed in a completely randomized design with 3 replicates. Results showed the significant effect of proline on vase life of tuberosa in both concentrations. The percentage of open flower increased in both proline concentrations. Finding showed the significant decrease in the wilted percentage of flower in both concentration of proline when compared with control flowers. The abscission percentage of flower also is very lower than the control flower. In according to the results, proline in both concentrations decreased the water loss and membrane leakage and the 10µM proline had the most effect. In flowers which were treated with proline, the activity of guaiacol peroxidase, catalase, ascorbate peroxidase and phenyalanine ammonialyase enzymes increased while the activity of polyphenol oxidase enzyme decreased. It seems that proline increment the postharvest life of tuberosa flower through the increase of antioxidant enzymes and decrease of polyphenol oxidase activity.

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In recent decade, establish and maintenance of turf grasses is faced with serious doubts due to reduction of precipitation and water resources. So, identification of drought-resistant native and rangeland species, and introducing them as turf grass not only is effective in reducing water consumption, but also help to preserve the genetic resources of the country. In order to evaluate the usability of native grasses of Iran as drought resistance grass, Wheat grass and Bromus were compared with Perennial ryegrass (Control). In this experiment, drought stress treatments were applied with irrigation withholding, and continued until the entire shrivel of all species shoots. During the stress period, shoot growth, leaf color, relative water content, prolin content, leaf width, shrivel percentage, root penetration, root fresh and dry weight, effective depth of root density and shoot fresh and dry weight were measured. The results of this research showed that reduction of shoot growth in Bromus occur sooner than two other species. The decline of relative water content and changes of leaf width were lesser in Wheat grass than two other species. Increasing of shrivel percentage in Wheat grass was done with more delayed than two other species. Prolin content in Perennial ryegrass was the most and in Bromus was the least. The measurements related to root and shoot traits was the least in Bromus and the most in Wheat grass. Moreover, the recovery in Wheat grass was done completely and faster. In aggregate, Wheat grass could be introduced as a drought resistance grass instead of Perennial ryegrass.

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Arsenic contamination in soils often leads to groundwater contamination and arsenic toxicity in plants, humans and animals. Plant hormones play a quantitative and qualitative role in the coordination of growth and yield in plants. In this research the effects of gibberellin and sodium arsenate in different genotypes of rice were studied. The work has been conducted as a factorial experiment based on completely randomized design with four replications in the field condition. The 29 days old seedlings from two genotype of Tarom as a local and Shiroudi as hybrid rice were treated with sodium arsenate (0, 50 and 100 &muM) and gibberellin (0 and 10 &muM). The proline content in leaves and roots, anthocyanin and phenol content in leaves , plant height, main panicle length, filled grains, empty grains, 1000 grain weight, yield, total biomass and harvesting index were measured. The results indicated that soduim arsenate had significant effect on all of the investigated parameters, so that with increasing soduim arsenate the proline content in leaves and roots, anthocyanin and phenol content in leaves , plant height, main panicle length, filled grains, 1000 grain weight, yield, total biomass and harvesting index significantly decreased and empty grains of rice increased. However, this negative impact in the genotype of Tarom was more than Shiroudi. Gibberlin treatment significantly improved all examined parameters in two genotype of rice under both 50 and 100 &muM sodium arsenate treatments, including proline content in leaves and roots, anthocyanin and phenol content in leaves, plant height, main panicle length, filled grains, 1000 grain weight, yield, total biomass and harvesting index. however, this positive impact in the genotype of Shiroudi was more than Tarom..

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Water deficit is a common and major constrain for agricultural production in arid and semi-arid parts of the world like Iran, to the extent that it might threaten the nation’s food security in years to come. Seed germination is a crucial growth stage that is often affected by environmental stresses, including drought. This study investigated the effects of four levels of water potential (i.e. 0, -0.2, -0.4 and -0.6 MPa) on germination, seedling characteristics, soluble carbohydrates, proline and polyphenols contents, and antioxidant enzymes activities of 12 fennel genotypes. Low water potentials reduced germination percentage and speed of germination, seedling fresh and dry masses, shoot length and superoxide dismutase specific activity, though it led to increases in root length, soluble carbohydrates, proline and polyphenols contents, and catalase specific activity. The 12 genotypes according to the degree of decreases in germination percentage at -0.6 MPa compared to control, were classified into three groups, including drought-tolerant (Shiraz, Yazd, Kerman and Mashhad), moderately-tolerant (Hamadan, Kashan, Bushehr and Urmia) and drought-sensitive (Birjand, Ardabil, AviSina and Isfahan). Mashhad, as a drought-tolerant genotype, indicated the greatest germination percentage, seedling fresh and dry masses, root length, soluble carbohydrates, proline and polyphenols contents, and catalase and superoxide dismutase specific activities among 12 genotypes studied. The results obtained in this study demonstrate some key aspects of the drought tolerance-related characteristics of fennel at germination stage that may help elucidate the whole plant performance of fennel at drought-stricken areas, when integrated with results from field studies.