فصلنامه زیست شناسی گیاهی ایران
سال هشتم شماره 2 (پیاپی 28، تابستان 1395)

Water deficit stress is one of the most important environmental factors limitting plant growth and crop production. In order to evaluate the tolerance of two Iranian melons to water deficit stress, an experiment in research filed of University of Zanjan was conducted. Treatments consisted of three Irrigation levels, starting irrigation at (100, 66 and 33 % Crop Evapotranspiration) and two accessions of Iranian cantaloupes (Tile-Zard and Tile-Sabz). In this experiment, total chlorophyll content, carotenoids, proline content, leaf relative water content (RWC), ascorbic acid, peroxidase and catalase activity, yield and water use efficiency (WUE) were evaluated. The results indicated that water deficit stress significantly increased proline content, peroxidase and catalase activity and WUE, but decreased RWC, yield and total chlorophyll content. The highest increase in proline content (34.8 %), catalase (18 %) and proxidase (42.3 %) activity and reduction in yield (61.6 %) and RWC (8 %) was obtained in 33 % ETc Irrigation. There has been significant difference between accesesions in relation to RWC, proline, total chlorophyll and peroxidase and catalase activity. The highest value of yield and WUE was observed in 'Tile-Zard'. According to the interaction results, both accessions, 'Tile-Sabz' and 'Tile-Zard' with 63.6 % and 59.7 % Reduction in fruit yield under deficit water stress, are.

Rice is an important crop and main food of more than half of the word and Umbrella sedge is one of the weeds growing in the rice paddies at North provinces of Iran. An experiment was set up in order to investigate the allopathic effects of aqueous extracts 50 % and 100 % of roots and shoots of umbrella sedge on tillering, flowering and grain ripening stages of rice. Experiment based on completely randomized in a factorial design with three replications was conducted in 2011 at the Rice Research Institute of Iran, Amol. The results showed that at tillering stage, with aqueous extract 100 % of umbrella sedge shoot was shoot fresh weight of rice 68.71g and its root dry weight 4.26g that compared to control plant (respectively 85.59g and 7.48g) decreased. At the flowering stage the fresh weights of root and leaf and dry weights of root, stem and leaf of rice were decreased by extracts of umbrella sedge and the fresh and dry weights of cluster increased. At grain ripening stage, extracts of umbrella sedge reduced the fresh and dry weights of rice and the weight of brown and white rice increased by 50 % root aqueous extracts. At this stage the percent of amylose, protein and lipid by all aqueous extracts significantly increased (P≤0.05) and control was 18.3, 7.705 and 0.505 % respective. The overall results showed that the aqueous extracts of umbrella sedge had different effects on triple stages of rice that depended on growth stages and the kind of organs.

Arbuscular mycorrhizal fungi (AMF) are the most important microorganisms of soil having an important role in soil fertility. In this research, the correlation between soil nutrient elements and Arbuscular mycorrhizal fungi colonization and spore numbers in the rhizosphere of Thymus kotschyamus Boiss. & Hohen. growing in the three regions (Taf, Vark and Kohkala) of Noujian watershed were studied during spring and autumn. Influence of arbuscular mycorrhizal symbiosis were also determined on vegetative characteristics and essential oil yield of T. kotschyamus.The results indicated that magnesium significant positive correlation with arbuscular mycorrhiza fungi spore density (.84) and percentage colonization (.92). Soil organic matter no significant linear correlation with arbuscular mycorrhiza fungi spore density and percentage colonization. Potassium negatively correlated with spore density and percentage colonization respectively; -0.85 and -0.90. Arbuscular mycorrhizal fungi colonization significant linear correlation with dry weight (.79). Essential oil yield of T. kotschyamus positively correlated with that of spore density and percentage colonization respectively; .93 and .91. Given the importance of mycorrhizal symbiosis and compilation this with soil elements, this information can be useful for development of medicinal plants in agricultural ecosystems.

Low-energy ultrasound shows multiple physiological effects on plant cells and tissues, and has numerous applications in plant biotechnology, especially in elicitation of secondary metabolites production. In this research, the effects of ultrasound on Iranian poppy cell suspension culture were investigated. For this purpose, cell suspension cultures were treated with ultrasound and then, cell viability and growth, activity of some antioxidant enzymes and amount of total protein, hydrogen peroxide, proline and thebaine were measured. The results showed that viability and dry weight (growth) of cells were significantly decreased under ultrasound treatment. In addition, increase in time after treatment led to severe reduction in cell viability and growth. Amount of proline and total protein were increased under ultrasound treatment, compared to the control. Analysis of variance revealed that hydrogen peroxide content of cells and activity of catalase, peroxidase and superoxide dismutase enzymes were significantly influenced by ultrasound, time after treatment and their interaction. So that, ultrasound treatment led to increased content of hydrogen peroxide and also elevated activity of aforementioned antioxidant enzyme in comparison to the control cells. Thebaine production in cells was significantly increased on 48 hours after treatment with ultrasound, compared to that of the control cells.

In today's world where human life is dependent on the industry, the problems impose in the human life along with theachievement of growing in the field of industrial works. One of the challenging problems is entry of pollutants into air that has the destructive effects on human life and environment especially plants. Plants show different responses against the air pollutants. Plant responses can be vary due to climate, geography and plant species. In this study, the effects of air pollutants in the Shazand industrial area (refinery, petrochemical and thermal power) stationin Markazi province has been checked on almond. For this purpose, the leaves of almond in Haftadgholle (control area), Shazand (closest city to industrial zone) and Kazaz (adjacent industrial zone) were collected. Also, soil samples were collected from three areas to determine lead and zinc amounts in soil. Results showed that proline, sulfur, heavy metals (lead and zinc) and lipid peroxidation enhanced significantly in Kazaz and Shazand in compared with Haftadgholle, while antioxidant activity of catalase, superoxide dismutase and guaicol peroxidase didn’t significant changes in three areas. The increase of sulfur amount in leaves, lead and zinc in soil of the Kazaz and Shazand regions could be one of the reasons to prove the presence of pollutants in these areas. The increase of lipid peroxidation indicative plant damage against the air pollution. The plant defense mechanism against of stress is the increase of non-enzymatic antioxidant proline. No change in chlorophylls and protein contents reflects increased resistance to the stress.

Vetiver plant is tolerant to acidity and temperature variations. Has rapid growth for biomass production and has high tolerance to organic and non-organic compounds in municipal waste leachate for example heavy metals. So this plant is good for landfill cultivation. In this study, physiological responses to municipal waste leachate were studied. Statistical design was a randomized complete block and each block treated with different concentrations of latex at levels of zero, 15, 30, 45 and 60 percent compared to the original latex waste. The leachate collected from the Shiraz landfill and brought into the greenhouse. The physiological characterization including leaf area, dry weight, chlorophyll, anthocyanin, proline, soluble sugars and total protein were measured. The result indicated that the dry weight, chlorophyll and anthocyanin decrease with increasing of latex concentration. The leaf area, leaf relative water, soluble sugars and total protein increased with increasing latex concentration. Proline concentration at 15 percent of leachate increased significantly compared to controls, whereas at higher concentrations decreased. According to the results, it is recommended that 45 percent of leachate in a landfill can be used to irrigate Vetiver. This is the maximum concentration of leachate that Vetiver plant can survive as green space. Primary filtration of leachate before using is recommended. If the aim is more growth or perfume application from root, less concentration of leachate is better.

The genus Salvia (Lamiaceae) comprises over 900 species in the world, with a relatively wide dispersion in the Iran’s flora. Until now, about 58 species of the genus have been reported and identified in Iran, in which 17 of them were endemic. In order to study, investigate and evaluate the intraspecific diversity, similarity and dissimilarity among Iranian Salvia officinalis accessions, an experiment was carried out using SDS-PAGE technique. In this study, the seeds from five accessions were collected from gene bank and were evaluated. The seed storage proteins were extracted by buffers and were measured. Phylogenetic relationships were analyzed according to presence and absence of bands on the gel. A dendrogram was prepared using calculation of the accession’s similarity index. Mean comparison were done by Tukey’s test. The seed protein contents showed significant differences (p≤0.01) among accessions. A total of 39 bands were indicated on the gel. The maximum diversity was detected in the accession No. 2 while, the lowest band’s number were recorded with the accessions No. 1 and 5. Based on dendrogram, the accessions were divided into two groups; one includes accession No. 1 and 4 other accessions were located in the second group further classified into two subgroup including accessions No. 2 and 3 in one clade and accessions No. 4 and 5 in the other ones.