JOURNAL OF PLANT ENVIRONMENTAL PHYSIOLOGY
Year:2014 | Volume:9 | Issue:1 (33)|Papers Count:8

In this research, the effect of different concentrations of manganese sulphate (MnSO4) on some physiological parameters in sunflower has been investigated. Seeds were germinated in petri dishes and the five days old seedlings were transferred to pots containing sand in a growth chamber with 16h light period per 24h and temperatures 25oC and 18oC for night, irrigated with Hoagland solution. Twenty days old plants were treated with MnSO4 solution at 0. 250, 350 and 1500 mM in nutrient solutions and harvested after 30 days for measurements of biochemical and physiological parameters. Results showed that gas exchange, photosynthetic pigments and soluble sugar content increased while insoluble sugar concentration decreased by different concentration of MnSO4 treatments.

To study the effect of electromagnetic waves on antioxidants contents of Mentha piperiata L., petri dishes containing moist seeds (seeds soaked in water for 5 h) with water and dry seeds without water were placed between the parallel coil electromagnetic waves at one mT intensity for four times in a day and each time half hours placed. Seeds after treatment were transferred to soil pots. In the leaves of the 30 day seedlings, antioxidant compounds were measured. Electromagnetic radiation exposure caused significant decrease in the rate of chlorophyll a and b, but in dry treatment was not significantly to control. Carotenoid, phenol, flavonoid and proline content significantly increased at treated samples in comparison with control. Also antioxidant enzyme catalase, superoxide dismutase and ascorbate peroxidase activities increased in treatment samples but in dry treatment was not significantly to control.

Priming is one of the seed enhancement methods that might be resulted in increased seed performance (germination and emergence) under stress conditions, such as salinity, temperature and drought stress. In order to study the effect of seed priming on seed germination index and some of physiological properties of super sweet corn in different levels of salinity, an experiment conducted with two factors that arranged as factorial  based on completely randomize design with three replications. Factors were consisted five levels of seed priming solutions (2% potassium chloride, 3% potassium nitrate, polyethylene glycol (8000) 10%, 1% potassium dehydrogenate phosphate with control) and four NaCl concentration (0, 50, 100,150, mM). Results showed seed priming and salinity had significant effect on shoot and root length and activity of antioxidants enzyme (ascorbat peroxidase and super oxide dismutase). In general results of this experiment revealed that seed priming improved the seed vigor and increased resistance to salinity stress at germination stage.

Drought stress is a main factor to inhibit crop production in many parts of the world, especially in arid and semiarid areas as Iran. Salicylic acid and its derivatives could participate in adaptation of plants against of environment stress and it could interact with some cellular metabolites to regulate plants reactions to their stress. In this research, effect of two concentration of salicylate (10-4 and 10-7M) under two moderate drought (25% soil saturation capacity) and intense drought (15% soil saturation capacity) on levels of antioxidant enzymes activities include catalase, ascorbate peroxidase, polyphenoleoxidase in leaf and root of Fenugreek were evaluated. To reach to this aim, at first, Fenugreek was planted in pots condition. In the middle of vegetative stage, plants put under two levels of drought stress during 60 days. Simultaneously, shoot plants were sprayed with two concentration of salicylate (10-4 and 10-7M) three time on week. After 30 days plants were harvested for antioxidant enzymes activity assay. Result showed that drought stress caused increasing of antioxidant enzymes activities of Fenugreek in leaf and root except ascorbat peroxidase. Spray of salicylate in different concentration caused decreasing of antioxidant enzymes activity in leaf and increasing of them in root.

In order to study the effect of different soils on physiological characteristics of cotton (Gossypium hirsutum L.) and determining of resistant genotypes; experiment were conducted using potted cottons as factorial in completely randomized design with 3 replications. Cotton genotypes include: Coker × 349, Opal, Bol 539, N200, Acalas sj2× seland, Sahel, Sepid. Beside this the effect of salinity from relatively non saline (0.6ds/m) to saline (16.5ds/m) would be regarded as the second aim. Results showed that effect of salinity on Na+ and Cl- content beside Catalase, and Peroxidase activities was significant at 1% probability but on polyphenol oxidase activity at 5% probability. Between genotypes Cl- content, Catalase and Peroxidase activities, showed significant differences at 1% probability. Differences between Na+ content, and Polyphenol oxidase activity, was also significant at 5% probability. Collectively results showed that with increasing salinity, activity of antioxidant enzymes increased in these crops leaves. Regarding total measured characteristics it can be concluded that Acala sj2×Seland, Sepid genotypes were more tolerant to salinity stress.

This research was carried out in 1388 in order to evaluate the effect of chlorophylls and carotenoids for determination of the quality and quality of the dry tea obtained from the selective colons of different research station in the center of tea research center.  Experiments were carried out as random blocks with 13 cares and 3 repeats during spring and summer. Samples were transferred to the laboratory for evaluating the amount of chlorophylls and carotenoides, in addition of teafelavin, tearobigin, tanin and qualitative and quantitatively. Data analysis was carried out using SPSS and MSTAT-C soft wares. Comparison of averages using Duncan and Shofea analysis showed that genotypes were placed in different groups. In the middle place of experimented 13 colon, chlorophyll and carotenoids showed the smallest and teaflavin, tearobigin, tannin and caffeine showed the highest quantity. To estimate of the attribute with the quality determinate. Fetors such as teafelavin, tearobigin, caffeine, tannins as water extract and the amount of the chlorophyll showed a positive correlation with carotenoid which possibly play a role in tea quality. It seems that the 10 hopeful colon with high (more) product and less pigments and another polyphenel and qualification features have been the appropriate function.

In this study algae Chlorella vulgaris Beijernick. after collection and purification  were grown  in  the culture medium BG-11 containing aluminium (AlCl3) in 0 and 300mM concentrations, pH 7.1, 25±2oC and autotrophic and heterotrophic conditions for 21 days. In order to autotrophic conditions, light intensity of 1500Lux illumination for 20 hours and 4 hours with alternating light and darkness to create heterotrophic conditions, darkness with 0.05 gram of different sugars, glucose and sucrose was provided. In either case, survival and growth (based on spectrophotometry and cell counting), pH medium, fresh weight, total protein content, pigment content (chlorophyll a, chlorophyll b and b-carotene) and internal aluminium content in the logarithmic growth phase were studied. Therefore, aluminium significantly increased (P<0.05) growth, pH and fresh weight in autotrophic treatments containing 300mM aluminium was compared to other treatments. Chlorophyll a content of autotrophic cells of Chlorella vulgaris Beijernick. was nearly double that estimated in  heterotrophic cells, while chlorophyll b content of autotrophic cells was  nearly half the value recorded for heterotrophic cells. b-carotene content of heterotrophic cultures decreased by 31% compared to that value of  autotrophic cells. A slight decrease in total protein content was observed under heterotrophic conditions. Survival during the 21-days cultures were maintained in darkness, but darkness conditions, the glucose tends was found. Sample in heterotrophic conditions (glucose), showed growth without lag phase which showed rapid acclimation of organisms in heterotrophic conditions. It seems as characteristics, single-celled green alga Chlorella vulgaris Beijernick. from different aspects, efficient and capable introduction to sample.

In order to study the effect of salinity and ascorbate on germination percentage, growth parameters and amount of proline and glycine betaien four-day-old seedlings of two cultivars of safflower (Padideh and Goldasht) was done experiments base on factorial in completely randomized design in four replications in research laboratory in Islamic Azad university of Gorgan. Experimented factor included two cultivars (Padideh and Goldasht) and four salinity levels of NaCl (85, 170, 255, 340 mM) and ascorbate (2 mM) in petri dish condition the results showed that growth parameters as germination percentage, length and dry weight of root and shoot, decreased significantly by increasing NaCl concentrate and with the addition of ascorbate reduced the inhibitory effects of salinity on the above parameters. Also with increasing salinity, proline, glycine betaine content was reduced. Application of ascorbate with salt reduced the amount of proline and increased glycine betaine content as compared to salinity treatment. Compare the results showed application of ascorbate with salinity stress could cause stress resistance in two cultivar of the safflower plant.