The aim of this study was to determine physicochemical characteristics in fruit of Page mandarin (Citrus reticulata) on different rootstocks. This study was conducted at Ramsar Research Institute in a completely randomized design with 4 treatments and 3 replications in 2015. The content of individual sugars in fruits was determined by HPLC. Total acidity (TA) and pH value of juice was also evaluated. Total carotenoids and chlorophylls content was measured using a spectrophotometer. Crude fat was extracted using Soxhlet`s apparatus .Crude protein was measured by Kjeldahl’s method. Total dry matter was determined by dehumidify of fruits in an oven at 80˚C. The results showed that, the highest of total sugars (107.35 mg/ mL), pH (3.50) and carotenoid (0.14 mg/ g) were in fruit of Page mandarin (Citrus reticulata) grafting on the Troyer citrange. According to results, the amount of total acid (0.73 %) of Page mandarin grafted on sour orange was higher than those of other rootstocks. پرونده مقاله

Triticum aestivum L. and Zea maize L. are both sensitive to salinity stress which is a major problem faced by farmers today. In the present study, the effect of chitosan, a biologic elicitor under salinity stress was examined on growth parameters and biochemical markers in maize and wheat seedlings. Seeds of wheat and maize plants were coated with chitosan 25%, 50%, and 75% solutions before they were planted and subjected to 0, 50, 100, 150, and 200 mM salinity stress under a 11/8 h photoperiod and at 25±2 °C temperature condition during 7 days. Then, the growth parameters including germination percentage, root and shoot growth as well as seedling weight were recorded. The biochemical markers including catalase and peroxidase activity and malondialdehyde, proline, and protein contents were measured at day seven of the experiment. Significant difference in relation with growth parameters was observed at high concentrations of chitosan in comparison with the control plants under salt stress. Catalase and peroxidase activity and protein content increased under salinity stress and chitosan at high concentration reduced catalase and peroxidase activity. Salinity stress induced lipid peroxidation and malondialdehyde accumulation while chitosan reduced malondialdehyde content of the plants under salinity stress. The synthesis of protein was significantly increased with increasing the chitosan concentration. Generally, the growth parameters of both seedlings were improved and unfavorable effects of salinity were reduced when the seeds were coated with chitosan. Application of chitosan at low concentrations increased antioxidant enzyme activity and proline content and decreased MDA accumulation. In conclusion, chitosan at an appropriate dose improved growth performance and biochemical marker fluctuation under salinity stress. پرونده مقاله

For considering the effect of drought stress on some morphological and biochemical changes in two pumpkin species, Cucurbita maxima L. and Cucurbita pepo L. a kind of experiment was done by field culture in three water dispersal levels with field capacity, 2/3 field capacity, and 1/3 field capacity, based on the factorial design in random block form with four replications. The results indicated that increasing the stress level, leaves water potential under drought stress decreased in comparison to the control sample in both species. But with increasing drought stress, root length increased too. Also during drought stress, root soluble carbohydrates content, ascorbic acid content, dehydroascorbic acid, catalase, polyphenol oxidase, and peroxidase enzymes activity increased significantly in 5% level, according to the results with increasing the stress, soluble carbohydrates content decreased in leaf. پرونده مقاله

Light is an energy source for photosynthetic organs and the type of optical wavelength plays an important role in growth. The effect of blue light investigated on delta-1-pyrroline-5-carboxylate (proline precursor) in 2-wheat cultivar, BAM (resistant to salinity) and Tajan (sensitive to salinity) in a culture medium. There were 5 salinity treatments including 0 (control), 50, 100, 150, and 200 mM NaCl. In addition, there were two light treatments, namely exposure to blue and white light. After five days of growth of wheat seedlings, the growth indices (fresh weight, dry weight, and longitudinal growth), proline, chlorophyll a and b, sodium, and potassium contents, peroxidase enzyme activity, malondialdehyde, and pyrolin-5- Carboxylate (proline precursor) contents were measured. Data were analyzed using Duncan statistical test. Blue light increased the amount of proline and PSC in the salinity-resistant cultivar. In the sensitive cultivar, the amount of potassium under the white light was higher than that under the blue light in different levels of salinity. The amount of sodium accumulated under the influence of blue light in different concentrations of salt in the resistant cultivar was higher than that in the sensitive cultivar. Peroxidation activity of the resistant wheat cultivar was higher and blue light did not increase this attribute, but the amount of malondialdehyde in the sensitive cultivar increased under the blue light regime and with increasing level of salinity. Fresh and dry weight of plants in the resistant cultivar was the highest under the white light. In addition, plant length in the resistant cultivar under increasing concentration of salt was more than that in the sensitive cultivar under both light regimes. پرونده مقاله