JOURNAL OF PLANT PROCESS AND FUNCTION
Year:2017 | Volume:6 | Issue:19|Papers Count:31

In order to investigate the effect of different levels of water deficit and foliar application of humic acid on the physiological characteristics of lima bean, a field experiment was arranged as split-split plot based on randomized complete block design with three replications in the research station of Shahrekord University in 2014. The main plot included four levels of drought stress (50, 70, 90 and 110 mm evaporation from pan class A) and sub plots included four levels of humic acid (0, 1, 3 and 6 lit/ha). In this experiment the traits of Chlorophyll a, chlorophyll b, carotenoids, membrane stability, relative water content of leaves, proline and soluble sugars were evaluated. The results showed that water stress caused significant decrease in all measure traits. Humic acid also significantly increased them. The interaction of water stress and application of humic acid on the carotenoids and proline were significantly affected, but had no effects on other traits. Foliar application of humic acid under drought stress conditions increased concentration of osmo-regulation including soluble sugars and proline and thus maintain osmotic pressure in cells, resulted the plant to resistant in drought conditions.

Water deficit can be considered as one of the most important abiotic factors limiting plant function, which has also adverse affects on growth and production of medicinal plants. In this research, in order to evaluate the effects of water deficit stress on of Artemisia dracunculus plant, a completely randomized design with three replications was performed in greenhouse conditions. The experimental treatments were different levels of irrigation based on control (90% of field capacity), T1: 60% of field capacity and T2: 40% of field capacity. Four weeks after treatment, physiological and biochemical indices were measured. Results showed that, water deficit stress had significant effects on measured traits and the average value of some traits such as: fresh and dry weight, leaf area, relative water content and shoot length were decreased under stress in both A. dracunculus collections in compare to control plants. The least average value of these traits was observed in T2 plants. Analysis of biochemical data also showed that, enzyme activity of peroxidase, proline and soluble sugars contents and the specific activity of peroxidase were increased in both A. dracunculus collections under water stress condition. However, enzyme activity of catalase, content of photosynthetic pigments (chl a, chl b and carotenoides), soluble protein content and the specific activity of catalase were decreased under stress. As a conclusion, Irrigation level at 40% of field capacity can be considered as stress level for this plant.Furthermore, A. dracunculus can respond to water deficit stress by increasing of the contents of proline and soluble sugars and the activity of peroxidase as one of antioxidant enzymes.

Salvia limbata. C. A. Mey is a herbaceous perennial plant whit proven medical effects, belongs to the family Lamiaceae. The objective of this study is to investigate the quantitative and qualitative variability of the essential oil of this species cultivated in new conditions (Karaj and Abhar) Compared with wild population (Semnan). The aerial parts of the plants were collected at the flowering stage and essential oils were obtained by hydrodistillation using a Clevenger-type apparatus. The essential oils composition were determined by GC and GC-MS. Cultivation of this species under new conditions led to increasing in oil content and variation of quality and quantity of essential oils when compared to wild population. Essential oil yield in wild condition and cultivated plants in Karaj and Abhar were 0.23%, 0.3% and 0.34% (w/w), respectively.The major components of the essential oil of wild population were 1, 8-cineole (18.98%), & alpha-Pinene (11.91%) and & beta-mircene (9.69%). Two main constituents of Essential oil of cultivated plants in Karaj and Abhar were & alpha-Pinene (23.49% and 2821%, respectively) and & beta-Pinene (19.21% and 22.42%, respectively). The highest amount of monoterpene hydrocarbons as well as lowest amounts of oxygenated monoterpenes and total sesquiterpenes were observed in essential oil of cultivated plants in Abhar.

Drought stress is a limiting factor for production in agriculture. In order to evaluate the impact of plant growth regulators, Salicylic acid and Paclobutrazol on growth and physiological traits of Sweet Basil (Ocimum basilicum) under drought stress condition, a factorial pot experiment based on Randomized complete design with 4 replication was carried out at research greenhouse of Mohaghegh Ardabili University, at 2012. experimental treatments were including water deficit stress (100, 60 and 30% percent of field capacity), two times foliar spraying with 100 and 200 ppm of salicylic acid and Paclobutrazol with two weeks interval. Controls sprayed by distillated water.Results indicated that the effects of water deficit stress, salicylic acid and Paclobutrazol foliar spraying on plant height, leaf dry matter, number of leaves, leaf area, stomatal conductance, relative water content and phosphorous content of leaves were significant (p& le0.01x). Parallel to raising water deficit stress, plant height, leaf dry weight, leaf surface area, phosphorus content and relative water content were reduced. Foliar spraying of salicylic acid and Paclobutrazol significantly increased relative water content, chlorophyll and proline content of basil leaves under drought stress condition. for conclusion, the research work revealed that application of salicylic acid enhanced tolerance against drought stress in basil plants, and the highest values for most of traits obtained by 200 ppm foliar spraying of salicylic acid.

The presence of heavy metals (metals with a density of over than 5 g cm-3) in the soil surfaces, are mainly due to industrial and mining activities, fuel combustion, etc.Although some of the metals are essential elements for plants, in the high concentrations have toxic effects on plants. Some of the plants those grown in mining areas are resistant to high concentration of heavy metals. The aim of this study was to assess the iron resistance of plant species in Esteghlale-e- Abadehe fire clay mine. Therefore, soil samples from six mine area and a control were collected. Plant species were collected too. After sampling and preparation of samples parameters: acidity, electrical conductivity, exchangeable and total iron of soil samples and plant iron content was determined. The results showed that exchangeable and total amounts of iron in mining areas were significantly higher than compared amounts in control site. It can be concluded from analyses of plant shoot iron concentrations that some of the plant species of mine areas are resistant to iron stress and use either avoidance or tolerance strategy for the resistance.

Borage (Borago officinalis L.) is a valuable medicinal plant and its production to meet the needs of the pharmaceutical industry has a high value. The objectives of this work were to evaluate water quality and different fertilizer systems on some physiological and biochemical characteristics of borage. The experiment was conducted as a split-plot arrangement based on compelet block design with three replications in 2012 at the research farm of Zabol University, Zabol, south Iran. The treatments were two irrigation sources: irrigation with fresh and saline water as main-plot, and four fertilization system: application of NPK at 80: 40: 30 kg ha-1, 40 ton of manure ha-1, NPK at 40: 20: 15 kg ha-1 plus 20 ton of manure ha-1 and no soil fertility as sub-plot. Salt irrigation water significantly increased antioxidant enzymes, carbohydrates and proline contents. The low quality of irrigation water reduces plant protein, chlorophyll fluorescence and moisture content, however mucilage content did not influence. Application of fertilization significantly increased all studied traits compared with the control except chlorophyll fluorescence. Combination of organic and inorganic fertilizer was more effective than sole application. Interaction of water quality by fertilization was significant only on ascorbate peroxidase. These results suggested that although irrigation with saline water decreased quantitatve and qualitative characteristics of borage, however, replacement part of chemical fertilizers with organic fertilizers can reduce environmental pollution.

To study the effect of salinity on photosynthesis pigments, fluorescence and antioxidants of three varieties of peanut leaf as an indicator of resistance to salinity, research was carried out as factorial arrangement based on completely randomized design with three replications in the greenhouse of University of Guilan in 2013. The experiment consisted of a combination of 4 different salinity levels (0, 50, 100 and 150 mM) and three cultivars of peanut (Local Guilan, ICGV96177 and ICGV03060). The results showed that the interaction between cultivars and salinity measurement on characteristics of chlorophyll a, chlorophyll a+b the maximum fluorescence (Fm) initial fluorescence (F0), Peroxidase and phenol were significant except for carotenoids. This study indicated that increasing the concentrations of NaCl, Phenol and peroxidase increased the amount of chlorophyll a and b, and chlorophyll fluorescence yield decreased, and in general the local cultivar of Guilan was the most resistant one under different levels of salinity.

In order to evaluate the effect of various levels of drought stress and foliar-application of ascorbic acid on some growth and biochemical parameters of marigold (Calendula officinalis L), an experiment was conducted with a factorial arrangement based on completely randomized design with three replications in Greenhouse of Bardsir Agricultural Faculty, Shahid Bahonar University in 2014. The experimental treatments were different levels of drought stress (irrigation based on: 1- filed capacity (control), 2-75%, 3-50% and 4-25% of filed capacity) and foliar-application of ascorbic acid (0, 1 and 10 mM). The results showed that the growth parameters (fresh and dry weight of plant, leaf area index and plant height), proline and soluble sugars showed significant different based on simple and interaction effects of the both treatments. But, chlorophyll a and b contents were only affected by irrigation treatments. The carotenoid contents showed significant difference by any the treatments. Fresh and dry weight of plant, leaf area index and plant height were significantly decreased with increased drought stress. However, increase in drought stress caused to increasing proline, soluble sugar and chlorophyll a and b contents. The results showed that in all drought treatments, foliar-application of ascorbic acid had a positive role on improving growth parameters and increasing contents of proline and soluble sugar, particularly in 10 mM application. Therefore, it seems that ascorbic acid can be considered as an antioxidant and plant growth regulator for mitigating the drought stress impacts on marigold planting.

The current experiment was designed to evaluate the effect of plant growth promoting rhizobactria (PGPR) on chlorophyll fluorescence and some physiological parameters in basil (Ocimum basilicum L.) leaf under salinity stress. The experiment was conducted in factorial arrangement based on completely randomized design.Treatments were four levels of salt stress (0, 40, 80 and 120 mM of NaCl) and three levels of PGPR inoculation (control, coinoculation with either Azotobacter+Azospirillum or Azospirillum+Pseudomonas+Bacillus). The results showed that increasing salinity stress significantly increased both minimum and maximum fluorescences (Fo and Fm) and quantum yield of non-regulated non-photochemical quantum efficiency [Y (NO)], while decreased variable fluorescence (Fv), maximum photochemical quantum yield of photosystem II (Fv/Fm) and photochemical quantum yield of photosystem II [Y (II)]. The trend of chlorophyll content and chlorophyll a and b (in control treatment) increased at low and medium level of salinity while decreased at higher salinity levels.However, with increasing the salinity level the relative water content (RWC) as well as the amount of carotenoids decreased and electrolyte leakage increased. Inoculation of basil plants with PGPR significantly reduced Fo and Y (NO) while increased Fv, Fv/Fm and NPQ as compared to the uninoculted control. Among the biological treatments, Azospirillum+Pseudomonas+Bacillus by 12% increase in Y (II) and 16% decrease in Y (NO), showed the most positive effects on plant photosynthetic system.Biological treatment also improved chlorophyll content, chlorophyll a and RWC and reduced electrolyte leakage. In conclusion, the current results indicated that the ameliorate effect of PGPR particularly coinoculation of Azospirillum+Pseudomonas+Bacillus on chlorophyll fluorescence and physiological parameters improvement of basil seedling leaves under salinity stress.

Salinity is one of the environmental factors that has a critical influence on plant growth and development. Researchers have shown that some plant growth regulators such as nitric oxide improves the plants resistance to environmental stresses such as salinity, heat, cold and drought. Sodium nitroprusside (SNP) commonly was used as a nitric oxide (NO) donor in plants. The aim of this research was to evaluate the role of SNP on salt tolerance of Zinnia elegans and its effects on some morphological, physiological and biochemical characteristics of this plant. A factorial experiment based on completely randomized design was conducted with five levels of salinity 0 (control), 25, 50, 75 and 100 mM NaCl and four levels of sodium nitroprusside (SNP) (foliar spray) 0.0 (control), 0.25, 0.50 and 0.75 mM with 3 replications. In salinity level of 50 mM, the length of stem and root was reduced 41.22 and 29.63 percent in compared to control. In salinity level of 50 mM, application of 0.5 mM sodium nitroprusside, increased total antioxidant capacity, glycine betain and proline 1.93, 3.98 and 2.12 times respectively compared to control. It also increased ascorbate peroxidase, catalase and guaiacol peroxidase 5.15, 4.69 and 2.78 times respectively compared to control. The application of SNP (especially at salt concentrations lower than 50 mM) ameliorated the adverse effects of salt stress, in Zinnia elegans plant.

In order to investigate the interaction effect of salinity and nitrogen on growth, mineral composition and salinity tolerance of soure orange seedlings a factorial experiment was carried out in completely randomized design with three replications. Factors consisted of four sodium chloride rates (0, 250, 500 and 1000 mg sodium chloride kg-1 soil) and four nitrogen levels (0, 50, 100, and 200 mg N kg-1 soil as ammonium sulfate). Sodium and chloride ions concentration in plant shoot and root were increased to toxic levels as the sodium chloride rates were increased form 0 to 1000 mg kg-1 soil. Subsequent result of this event was the significant reduction in plant dry weight. In all sodium chloride rates, nitrogen consumption up to 100 mg kg-1 soil increased plant dry weight.However the increasing effect of nitrogen on plant growth was dependent on applied sodium chloride level. As the level of applied sodium chloride was increased, the improvement effect of nitrogen on plant growth was decreased. Although nitrogen had no conciderable effect on sodium concentration in plant shoot and root, increments in nitrogen application made a decrease in shoot chloride concentration and an increase in root concentration of this element. Salinity decreased nitrogen, phosphorus, potassium, iron, manganese, zinc and copper concentration in plant shoot. So it can be concluded that the salinity influence on plant growth reduction can partly be related to the decrease of essential nutrients concentration to below sub optimal levels.Nitrogen improved the decreasing effect of salinity on concentration of plant essential nutrients by increasing their concentration in plant tissues.Therefore it can be concluded that under salinity condition, part of nitrogen influence on reduction of salinity adverse effects is related to the maintenance of essential nutrients concentration in plant tissues.

Silicon is a chemical element that has many positive effects on some qualitative and quantitative characteristics of many plant species such as ornamental plants. The aim of this research was to investigate the impact of silicon spray on growth and photosynthetic characteristics of chrysanthemum. This study was performed as a factorial completely randomized design with 2 factors: silicon source in 2 forms (sodium and calcium silicate) and the concentration of silicate in five levels (0, 50, 100, 150 and 200 mM) in perlite: coco-peat medium with 3 replications and 2 observations. Traits such as leaf area, leaf number, leaf temperature, fresh and dry weight of leaves, chlorophyll index, chlorophyll a and b, net photosynthesis, transpiration and stomata conductivity were measured. The results showed that sodium and calcium silicate reduced leaf temperature but, increased other measured indices compared to control. The effect of silicon on these indices may be because of its effect on plant metabolism and photosynthetic system such as the concentration of Rubisco enzyme, increasing the transmission of photoassimilates from source to sink, increasing photosynthesis efficiency, changing the distribution of photosynthetic products, reducing oxidative substances, increasing carbohydrates and changing the concentrations of internal hormones.

Salinity is a complex phenomenon that involves not just an osmotic effect, but also toxic ion effects and nutritional imbalance. In order to evaluate the effects of severity and duration of sodium chloride stress on some biochemical and photosynthesis parameters of tobacco a factorial experiment was conducted using a randomized completely block design with three replication with using a hydroponic culture in Biotech Center of Urmia university. In this study, the effects of 5 salinity levels (0, 50, 100, 150 and 200 mM NaCl) and three time periods (2, 5, and 12 days) were evaluated. The results showed that under sodium chloride stress the dry weight and photosynthetic pigments compared to the control were reduced, while proline content was increased. The results of analysis of variance showed that sodium chloride levels, duration of stress and the interaction of stress and duration of salinity have significant differences on stomatal conductance, transpiration rate, CO2 concentration and water use efficiency (p≤0.01). The sodium chloride levels and the interaction of stress and duration of sodium chloride stress have significant differences on net photosynthetic rate and mesophilic conductance. The net photosynthesis, stomatal conductance, transpiration rate, intercellular CO2 concentration and mesophilic conductance in 200 mM sodium chloride at 12 days after stress compared to control 74%, 97%, 90%, 48% and 59% decreased, respectively.These results indicate that stomatal limitations might be the main cause of decrease of photosynthesis in tobacco plant under sodium chloride stress.

Selenium (Se) is an essential element for human and livestock health with antioxidant and anticancer effect. Although Se is not an essential element for plant growth, but improve the plant growth. A hydroponic experiment was conducted in the greenhouse of Isfahan University of Technology in winter of 1391. The completely randomized design was arranged. Se in four concentration 0, 2.5, 5 and 10 µM and Nano-Se in0, 1, 4, 8 and 12 mM was added to nutrient solution. The results showed that Se improved stem diameter, fresh weight of shoot, chlorophyll content and phenol.Nano-Se improved root volume, fresh weight of root, relative water content of shoot, internal stomata CO2, and leaf temperature and mesophyll conductance. Se and Nano-Se were effective in 10 and 4 µM, respectively. Root volume increased in 8 µM Nano-Se by 72.4%. Chlorophyll content increasd by 73% in 10 mM Se. N-Se was more effective than Se on mesophyll conductance and increased in 4 mM Nano-Se by 9.9%. Conclusively, Nano-Se and Se in 10 and 4 mM was more effective respectively on most vegetative, antioxidant and photosynthetic activity of tomato.

In natural environment and agricultural conditions, plants are frequently exposed to environmental stresses. One of the main factors reducing the worlds agricultural production is drought. In this research the effect of drought stress on physiological parameters of some cultivars of sorghum was studied in vitro. The seeds of sorghum were sterilized and then were cultured in MS medium supplemented with mannitol at percentages of 0, 2, 4, 6 and 8 (various levels of drought).Percentage of seed germination was measured seven days after planting. After 3 weeks, morphological and biochemical parameters were measured in treated plants. The results showed that increasing of drought stress in different varieties, the percentage of seed germination was reduced. Red sorghum on a percentage of germination was more susceptible than others. In all of the variety of sorghum, length of shoot and root, dry and fresh weight of shoot and root, content of chlorophyll and carotenoid were decreased. Content of Flavonoid, sugar, anthocyanin, proline, protein and activities of catalase, ascorbate proxidase and superoxide dismutase increased in shoot and root. The results showed that all of varieties of sorghum were resistant against of drought stress with typical changes in morphological and physiological parameters.

In order to assessment of the relation among low temperature with (Fv/Fm, leaf chloropyll and caratenoied contents) of clover spp, an experiment was arranged as split plot in RCBD with four replications include plant date as main plot (15 and 29 Sep.) and clover spp as sub plot (Persian spp with 7 cultivars, Berseem , Red and Crimson clover with 1 cultivar) at Seed and Plant Improvement Institute of Karaj in during 2010-2011. The measurement of physiological traits in clover spp recorded at rosset growth stage in days with temperature under zero centigrad. The results showed that low temperature stress cuased significant decrease clover spp that the decrease rate could be because of low temperature stress at field. At among clover spp, Red clover cv. Nassim had the least less chlorophyll content. The results also showed that chlorophyll (a) is more affected to low temperature than (a/b), (a/b) and (b). During stress (S1, S2 and S3), Fv/Fm of clover cultivars was 0.734, 0.788 and 0.555 respectively, that represent the effect low temperature stress to Fv/Fm in all treatments especially S3. In addition, the results showed that in low temperature stress, Red clover cv Nassim had less yield Fv/Fm than to other cultivars. In general the using of Fv/Fm, chloropyll content and caratenoied leaf parameters is recommended for screening and evaluating of clover cultivars in under low temperature stress conditions at fields.

Endophytic fungi as the most important soil microorganisms through establishing a symbiotic relationship with various plants play an important role in improving growth and mineral nutrition of their host plants. This research investigates the effect of Piriformospora indica and mycorrhizal fungi treatments on phosphorus efficiency indices and increasing phosphorus deficiency tolerance stress in wheat plant (Triticum aestivum L). For this purpose, a factorial greenhouse experiment in a completely randomized design with two fungal treatments including P. indica (inoculated & non-inoculated) and mycorrhizal fungi (non-inoculated, Glomus intraradices, Glomus mossea and G. intraradices+G. mossea) in three replications was conducted under phosphorus-deficient conditions. After 60 days of planting and measuring some parameters like root and shoot dry weight, shoot P content and the activity of guaiacol peroxidase (GPX) in shoot, phosphorus efficiency indices were calculated. The results showed that the impact of studied microorganisms on the mentioned indices was significant at the 0.05 level, so that co-inoculation treatment of G. intraradices and P. indica in increasing growth parameters, P uptake efficiency, roots and shoots phosphorus-efficiency and stress tolerance index (STI) was reported as the most efficient microbial treatment. Individual treatment of P. indica due to higher potential in transferring P from root to shoot, had a more effective role in increasing shoot phosphorus concentration compared with other treatments. The results of this research shows that under P-deficiency conditions, the studied fungi resulted in increasing wheat tolerance to P- deficiency by increasing P-uptake, improving growth of roots and shoots and increasing GPX activity. It is worth mentioning that the effect of the studied fungi on wheat cultivars and their antioxidant responses to P deficiency stress may not be the same.

In this study, the effect of leaf spray of two salicylic acid concentrations, 100 and 500 mM, was studied on the some physiological and biochemical properties of grape cv. Ghizil Uzum in saline (EC=10) and non-saline (EC=2) conditions. The experiment was conducted in a Completely Randomized Design with 4 replications under greenhouse condition. The results showed the significant decreases in fresh and dry weights, water content, photosynthetic pigments, photochemical efficiency of PSII and total protein, starch and K+ concentrations of leaves in saline condition. But, the concentration of free amino acids, soluble sugars and Na+were increased. The salt affected the plant antioxidant system by induction of superoxide dismutase, peroxidase and catalase activities and increasing malondialdehyde and H2O2 contents of leaves. Salicylic acid application in both concentrations in non-saline condition and in 500 µM in saline condition has not notable effects on studied parameters. Application of 100 mM salicylic acid in saline condition could ameliorates the negative effects of salt stress in grape cv.Ghizil Uzum by increasing the osmolytes and carotenoids concentrations, photochemical efficiency of photosystem II, capacity of antioxidant system and specially decreasing the Na+ions transfer to growing plant organs.

To study the effects of water stress on compatibility metabolites and the antioxidant enzyme activities of wheat variety trial a factorial experiment was conducted in a completely randomized design in 1393. The experiment consisted of three levels of stress (85, 60 and 35% of field capacity) and five varieties of wheat (Orom, Zarea, Mihan, ZSZOBKAYKA, JS3l7G217,) Analysis of variance showed, Proline, soluble sugars, lysine, methionine, protein and antioxidant enzyme activities of catalase, peroxidase and polyphenol oxidase and osmotic potential, the main and interaction effects of the drought were at 1%. Stress causes an increase in proline, soluble sugars, the activity of catalase, peroxidase and polyphenol oxidase and reduces the amount of lysine, methionine, protein and osmotic potential. The highest levels of proline, methionine, catalase, peroxidase, polyphenol oxidase from the figure of 35% was observed in tension Zarea. The highest sugar solution from the Orom, the highest lysine than ZSZOBKAYKA and highest protein content of 35% was obtained in tension at Mihan. It was also observed, the osmotic potential of the Mihan. Based on regression analysis osmotic potential under the influence of polyphenol oxidase activity and protein levels and Mihan with the highest level of protein and low PPO activity showed the highest potential osmotic stress.

To investigate the effect of salicylic acid (0, 50 and 100 mM) on some physiological characteristics of henna, medicinal-industrial plant, under drought stress (0, -2 and -4 bar induced by PEG 6000) a factorial experiment based on completely randomized design was carried out in the research greenhouse of agriculture faculty of Shahid Bahonar University of Kerman. The content of photosynthetic pigment, protein, antioxidant activity of catalase and poly phenol oxidase and dry matter production were measured as some physiological response of henna. All measured traits affected significantly by drought stress (p<0.01). The highest amount of these traits except the activity of catalase and poly phenol oxidase were recorded for non-stress condition. The only trait that was not affected by salicylic acid significantly was the activity of poly phenol oxidase. The application of 50 mM salicylic acid led to the highest amount of these traits. The interaction of salicylic acid * drought stress was significant only for chlorophyll a, total chlorophyll, protein content, catalase activity and dry matter. Based on the obtained results, it can be concluded that application of salicylic acid on henna could largely improve the deleterious effects of drought stress through modification of physiological responses.

temperature, high irradiance, low water vapour pressure, and lack of precipitation in most months characterize arid ecosystems. Under these conditions, trees such as pistachio suffer drought combined with salinity stress. In order to study the simultaneous effects of salinity and drought stresses on photosynthetic apparatus function in P. khinjuk, seedlings of the species were exposed to osmotic stress induced by a combination of salt and poly ethylene glycol (Ctrl (without any treatment), low osmotic stress (LOS), moderate osmotic stress (MOS) and high osmotic stress (HOS). Chlorophyll fluorescence yields were measured / calculated for the following parameters: F0, Fm, Fv, Fʹm, Fʹ0, Fʹm, Fʹv, Fs, F0 /Fm, Fv/ Fm, Fv/F0, Fʹv /Fʹm, & PhiPSII, ETR and Photoinhib-PSII%. A one way ANOWA showed that all the mentioned parameters were differently reacted to osmotic stress treatments without any visible symptoms of foliar phytotoxicity. The highest decrements or functional alterations in fluorescence parameters (in frame of defense mechanism or inactivation of photosynthetic apparatus) were observed at HOS.

Conservatiion with respect to physiological aspects of crops is a crucial factor for ideal photosynthesis and appropriate yield in arid and semi-arid agro-ecosystems.In order to investigate the effect of planting pattern on stability of physiological parameters of fenugreek and black cumin under drought stress, an experiment was conducted in the University of Shahrekord in 2014. Three drought levels, i.e.W1: complete irrigation (irrigation based on 100% of the field capacity), W2: moderate stress (irrigation based on 75% W1), W3: severe stress (irrigation based on 50% W1) were assigned to as main factor and five planting patterns including fenugreek and black cumin sole cropping, and three intercropped ratios (1: 2, 1: 1, 2: 1 fenugreek: black cumin) as sub factor. Results showed that by increasing drought stress, the amount of chlorophyll a and chlorophyll b were increased especially for fenugreek: black cumin intercropped as by as their sole cropping. In fenugreek, the greatest amount of proline was obtained in fenugreek: black cumin (1: 1) and sole cropping treatments as high as 10.51 and 11.5 mg/g, respectively, and the lowest amount (9.75 mg/g) was recorded in fenugreek: black cumin (2: 1).Moreover, the highest rate of essence was recorded in sole-cropping (12.9 g/kg) and fenugreek: black cumin (1: 1) (12.6 g/kg). Although the essence rate of sole cropped plant was higher in back cumin, but intercropped plant had more essence in drought conditions. Also more relative water content and less soluble sugar and essence were seen in intercropping patterns, with increasing drought stress. Generally, it could be concluded that creation of interspecific competition could be an important strategy to protect physiological parameters against drought stress damages.

Silicon (Si) has not been considered as an essential nutrient for plant growth however, it has been shown that supplying crops with adequate Si can improve environmental stress tolerance. On the other hand, exposure to toluene, as a hazardous organic pollutant widely found in the water resources, is an environmental stress for plants growing around many industries. The aim of this nutrient solution culture experiment was to investigate the effect of Si nutrition on alleviating injuries induced by toluene contamination on alfalfa (Medicago sativa L.). The plant seedlings supplied or unsupplied with 1 mM silicon (in the form of Na2SiO3.5H2O) were exposed for 30 days to three levels of toluene (0, 225, 450 mg L-1) in the nutrient solution. The results showed that shoot and root fresh mass, plant height, and root length significantly decreased in the present of toluene contamination.Exposure to toluene significantly decreased relative water content of the leaves, leaf photosynthetic pigments concentration, and Fe and Zn concentration in the shoot and root. Toluene contamination led to elevated peroxidation of root cell membrane. In the present of toluene, addition of Si enhanced water use efficiency, membrane stability, chlorophyll concentration and photosynthetic activity of the leaves. These changes induced by Si may lead to higher accumulation of Fe and Zn in the plant shoot.

Chilling stress usually can be seen in tropical and subtropical crops or in crops which are grown in afore mentioned areas. Generally, the crops are very sensitive to chilling stress during their active growth and early stages of their development. In this research, a study on the effects of chilling stress and salicylic acid on physiological and biochemical traits of corn hybrid single-cross 400 in factorial arrangement in a completely randomized design in the research greenhouse of Ferdowsi University of Mashhad has been investigated. To this, chilling stress in two levels (i.e. non-stress control, and chilling stress at 5oC in four-leaf satge using thermogradient freezer for 12 hours) as the main factor and three levels of spraying salicylic acid solution (non-spraying control, 200 and 400 micro molar spraying) as subsidiary factor was applied. The results showed that the concentrations of malondialdehyde, Di-tyrosine and proline increased and the activity of superoxide dismutase, glutathione peroxidase and catalase enzymes decreased significantly in chilling stress.Spraying of 200 and 400 micro molar salicylic acid solution ameriolated the negative effect of chilling stress. Electrolyte leakage increased, while, water content and dry matter accumulation and leaf area has been decreased in the presence of chilling stress. Spraying of salicylic acid solution caused an increase in chlorophyll content. Indeed, a significant correlation between the cold damage, salicylic acid treatment, and investigated traits were appeared that represent the corn seedling’s positive reaction to salicylic acid in chilling stress condition.400 mM salicylic acid proline sprayed most of the 39.5 micromoles per gram of fresh weight, respectively.

A factorial experiment in hydroponic conditions was conducted to evaluate the activity of antioxidant enzymes, membrane stability and Na concentration in seedling of some rice cultivars, in 2014 summer in Ramin Agriculture and Natural Resources University of Khuzestan. Experimental factors were included salinity levels of NaCl (0, 4 and 8 ds.m-1) and rice cultivars (Amol3, Daniel, Shafagh, Fajr and Red Anboori). Some attributes including, hydrogen peroxide, malondialdehyde, peroxidase, electrolyte leakage, Na concentration and shoot dry weight were measured. The result showed that salinity levels significantly decreased shoot dry weight and increased antioxidant enzymes, membrane peroxidation, electrolyte leakage, and Na concentration. Rice cultivars responded differently to salinity levels. Red Anboori and Amol3 Cultivars had the highest antioxidants and the lowest lipid peroxidation.These two cultivars in control condition had lowest shoot dry weight (5.15 and 5.51 g.plant-1). However, these cultivars had no significant difference with other cultivars in 8 dS.m-1 salinity condition. On the other, Danyal and Fajr cultivars were obtained greatest reduction in shoot dry weight under severe stress (51.9 and 49.4 percent respectively). So Red Anbory and Amol 3 cultivars by increasing enzymatic defense system and reduce damage to cell membranes as tolerant cultivars at the seedling stage compared to another cultivars will be introduced.

Saint julien A is one of the important semi-dwarf rootstocks belonging to prunus family in terms of resistance to some common disease and pests in stone-fruits in addition to its high compatibility to different stone-fruit cultivars. In this study, the effects of methyl jasmonate, TIBA and scopoletin were studied on some parameters of shoot regeneration, IAA-Oxidase activity as well as improving some growth deficits such as eradication of sluggish grown of regenerated shootlets, under in vitro condition. Two types of explants were subjected to experiments: normal and sluggish grown explants. Results revealed that in the normal grown explants scopoletin and methyl jasmonate (1.0 mg/l) affected significantly the shoot number regeneration (4.12±0.17 and 3.18±0.18) and the shoot length (4.13±0.11 and 3.19±0.06 cm) respectively on MS medium. These chemicals have had also significant effects on mean shoot number (3.5±0.2 and 2.06±0.06) and shoot length (1.77±0.02 and 1.45±0.03cm) respectively in the sluggish grown explants compared to control and TIBA. Results also indicated a considerable increase in IAA-Oxidase activity for sluggish grown shoots in comparison with control. Besides, the incorporation of TIBA to media decreased significantly the activity in IAA-Oxidase in both normal and slow grown explants along with 30 days.

Thyme is one of the best known genera within Labiatae family, because of its more than 250 species and its antimicrobial and antispasmodic uses. At the present time, demand for thyme products are increasing and hence research demand is increasing.Environmental factors such as drought can affect plant growth and production.Phytohormones take a crucial role in this stress. Indicated T. serpyllum as the most tolerant and T. vulgaris as the most susceptible genotypes to water deficit stress been used. At the end of stress period, shoot dry weight, water content, water potential and soil moisture were measured. Based upon these traits, tolerant plants known as water saver plants, while, sensitive plants behaved as water spender plants. This experiment was conducted at the University of Birmingham, School of Biosciences in 2013. During the stress, leaf samples were harvested and analyzed through mass spectrometry based metabolomics approach. The results of tolerant plants indicated significant increase in drought-stressed plant rather than control plants as follows: 173% increase in salysilic acid, 133% increase in neoxantin (abscisic acid substrate), 166% of auxin and 180% of gibberellic acid. Nevertheless, sensitive plants showed significant increase in jasmonic acid 132%, salysilic acid 242% and decrease in neoxanthin 62% and gibberellic acid 36%. Auxin had non-significant difference between stressed and control plants of sensitive populations. Increasing of neoxanthin in tolerant plants occurred with water content maintenance and decreased shoot dry weight. This experiment confirmed the key role of abscisic acid and salysilic acid in drought stress tolerance mechanism. Even though, it seems overall response of plant to drought stress is the result of all the phytohormones interaction. Increasing ABA precursor caused growth inhibition in drought tolerant plants, which eventually provided less water usage. Since, sensitive plants didn’t exhibit neoxantin elevation, which seems it is due to being lower than water potential threshold.

The pollution caused by the presence of heavy metals in the air, water and soil is one of the world's ecological problems. In this study, the effect of different concentrations of calcium on the absorption and accumulation of Cd and Zn in M. flavida from Brassicacea was studied. For this purpose, concentrations of 100, 400 and 1600 µM calcium and 1, 5 and 10 µM Cd and 10, 20 and 40 Zn was used. This survey was conducted as factorial experiment based on a complete randomized design. The seeds are grown in pit and seedlings in the two-leaf stage were transferred to hydroponic culture and using a Hoagland solution was watered for two weeks. Two weeks after treatment with these metals, root length, shoot and root dry weight, chlorophyll content, leaf area, relative water and metal accumulated in the plants were measured. The results showed that by increasing the concentration of calcium decreased the toxicity of Cd and Zn. In 1600 mM calcium and 1 mM of Cd was observed longest root but with increasing cadmium, root length decreased. The shoot and root dry weight, chlorophyll content, leaf area and plant relative water content decreased with increasing concentration of Cd. The amount of Cd accumulated in the shoot and root showed that with increasing concentrations of Cd in the medium increased the accumulation of this element by the plant. Generally calcium reduced the toxicity of Cd and Zn.

In order to investigate application of nitrogen rates at different growth stages effects on dry matter remobilization and effective traits at dry matter accumulative of grain in spring barley (Hordeum Vulgare L.), an experiment was conducted as factorial based on randomized complete block design with three replications at the research farm, University of Mohaghegh Ardabili during 2012 cropping. Experimental factors were: nitrogen rates in four levels (0, 60, 120, and 180 Kg N.ha-1) as urea and nitrogen application at different growth stages in four levels (T0 at planting stage+at stem elongation), (T1: at planting+stem elongation+at ear emergence stage), (T2: at planting+stem elongation+in ear emergence stage), (T3: at planting+stem elongation+ear emergence stage).Results showed that dry matter remobilization rate from stem, contribution of dry matter remobilization from shoot organs at grain yield, components of grain growth, nitrogen use efficiency, yield and yield components were significantly affected by experimental factors. Maximum of dry matter remobilization from stem and shoot organs was obtained in control treatment and the least of it were obtained in higher nitrogen rates as T1. The highest rate and grain filling period, yield and yield components was obtained in higher nitrogen rates as T1. Maximum of nitrogen use efficiency (31.45 kg/kg) was obtained in application of 60 kg N.ha 1 as T1 and the least of it (23.72 kg/kg) was obtained in higher nitrogen rates as T0. Based on the results, it was concluded that application of 180 kg N ha-1 as T1 can be recommended for profitable barley production in the study area.

Salinity is one of the most harmful environmental factors limiting the productivity of crop plants.Selenium (Se) is a metalloid element which regarded as an antioxidant in plants, animals and human nutrition. Se have shown enhanced resistance to certain abiotic stresses including salinity, drought and etc. The present study investigates the effect of exogenous selenium mitigating the salt induced damage in sunflower plants. In this research, the plants were treated with NaCl (0, 25, 50 and 75mM) and Na2SeO4 (0, 10 and 20mM) in nutrient solutions. Plants were harvested after 23 days for biochemical assay. The results showed that in plants only treated with sodium chloride, with increasing of sodium chloride concentration, photosynthetic pigments and protein contents decreased as compared with those of control plants. In plants exposed to sodium chloride and Na2SeO4, photosynthetic pigments and protein contents were higher than of plants only exposed to sodium chloride.Antioxidant enzymes activities including catalase, guaiacol peoxidase, ascorbate peroxidase and superoxide dismutase increased in plant exposed to sodium chloride. In plants exposed to sodium chloride and Na2SeO4, the enzymes activities were higher than of plants only exposed to sodium chloride With increasing NaCl concentration, lipid peroxidation increased, however, with addition of Na2SeO4 to NaCl, MDA content decreased and antioxidant enzymes activity, significantly increased. The results showed that sodium selenate can protect plants against stress and increase antioxidant capacity.

Juniperus communis L. from the plants growing in Iran and in the highlands in the valleys of Gorgan hall altitude pass, Hezarjarib and Talysh Spill distributed. In this study, the quality and quantity of active ingredients (extracts) J. communis aerial parts of the plant in different habitat Hezarjarib in behshahr was summer pastures. Branches covering height in 1950, 2050, 2150 and 2250 meters above sea level collected then dried in the open air under the shade. Extract of aerial parts of the plant as meo h-Extract (methanol) to identify compounds extracted from the extract by GC/MS were used. Data analysis was done using SPSS software to analyze and compare the characteristics of an extract from the analysis of variance (ANOVA) and T-test was used.41 combined extract of aerial parts of the plant were identified, among which compounds are & alpha-pinene, sabinene, limonene, & beta- cubebene and diallyl phthalate, and also has the highest percentage of sites significant effect on the composition of phthalate diethyl and & beta-thujene in extract has branches. Compounds abieta-8, 11, 13-triene, d- (+) - carvone, hexadecanamide, elemol and trans sabinene hydrate were found only in one locality. Also, a significant correlation was observed between 12 combination with some soil elements.