Journal of Plant Biological Sciences
Year:2016 | Volume:8 | Issue:29 |Papers Count:7

In order to investigate the effect of Piriformospora indica under salt and drought stresses on some vegetative characteristics and physiological parameters of stevia (Stevia rebaudiana Bertoni) medicinal plant, an experiment was conducted in factorial arrangement based on completely randomized design with three replicates at Genetics and Agricultural Biotechnology Institute in Sari Agricultural Sciences and Natural Resources University. Factors include three levels of osmatic potential (0, -5, and -10 bar) and with three osmotic sources including NaCl (Na), Mannitol (M) and NaCl+Mannitol (N+M) and inoculation of mycorrhizae like fungi at two levels (non-inoculated and inoculation with fungi). The plantlets were treated for 30 days and then some morphological and physiological parameters were measured. Results of ANOVA showed that there was a significant interaction between osmatic source and levels with fungi inoculation for the most determined parameters. Inoculation of stevia plantlets with P. indica at osmatic level of -5 bar caused either by M or M+Na markedly improved dry weight of leaf (112 and 156%, respectively) and aerial parts (49 and 144%, respectively) as compared to the uninoculated control. Fungi inoculation positively improved vegetative parameters of stevia plant under most osmatic levels and sources. The most ameliorate effect, however, was observed where M as drought stress or M+Na were adjusted to -5 bar. Therefore, the results of this study represented a positive effect of P. indica inoculation in inproving osmotic tolerance of stevia medicinal plant.

Biohydrogen production by biological processes are known as a renewable energy source. The aim of the investigation was to find and optimize the most appropriate medium for the algae growth to produce the maximum amount of hydrogen. First of all, the bioinformatics and biosystematics studies were taken for identifying the collected microalgae which was detected as Chlorella with the following features: spherical appearance, spent protozoan, Cup-shaped chloroplast with no flagella. On the other hand, the molecular analysis by PCR and 18S sequence typing of interested microalgae demonstrated 100% similarity to that well known sequences for Chlorella vulgaris. Second, we assessed some culture media including BBM, Chu10, TAP, and Sorokin and Krauss for optimum growth conditions for Chlorella vulgaris. In general, our results showed that BBM medium had the highest efficiency for producing microalgae biomass under following conditions: pH=8, temperature of 30 ° with 16 to 8 h light to darkness periods ratio. Third, we designed a more efficient photobioreactor apparatus toward inducing more powerful bio-hydrogen production by hydrogenase enzyme activity of our given microalgae. Then, the performance of the apparatus as well as the gene expression was scrutinized under different conditions (light, pH, sulphorous, etc.). For this, after extracting RNA and constructing cDNA, hydrogenase gene was amplified with PCR and the product was evaluated by agarose gel. However, the relative expression of the gene measured by Real Time PCR showed the influence of light, pH and sulphourous on the expression as compared with control.

Kalpoureh (Teucrium polium L.) as a medicinal plant belongs to family Lamiaceae. This plant has short growth period and endangered, so it seems the method of plant tissue culture is efficient for that. On the other hand Teucrium polium with high antioxidant properties has many health benefits. In this study, the effect of culture medium, different concentrations of 2, 4-D and the type of explants on callus induction were evaluated. It was found that effective treatment for more fresh weight of callus was the leaf explants on B5 culture with concentrations 1 and 0.5 mg L-1 of 2, 4-D. In no hormone treatments, the percentage of callus induction was lower than others and the highest percentage of callus induction was on medium containing higher levels of the hormone. Analysis of biochemical properties (total phenolic content, antioxidant capacity based on two tests; DPPH and PPM) was also concluded that callus of terminal bud on B5 medium with no hormones had the highest total phenol (82.66 mgGAE/100 g FW). Based on DPPH test, the most free radicals scavenging potential was seen for the leaves collected from the habitat and the callus of terminal bud explants on B5 medium with concentration of 0.5 mg L-1 2, 4-D. Investigation on total antioxidant capacity also revealed that callus of terminal bud on MS medium, 2 mg L-1 2, 4-D, leaves and stems of plants collected from habitats showed more activities. These conditions can provide the suggestion for the use of these media to produce more secondary metabolites with antioxidant properties.

Members of Polyphysaceae (Acetabulariaceae) are very beautiful and attractive unicellular plants which grow on coral reefs of the intertidal regions especially in tropical oceans and seas. In this study morphological features of some collected and identified species of the family from the Iranian seashores of Persian Gulf has been reported. Parvocaulis parvulus, Acetabularia caliculus and Parvocaulis clavatus are three identified species in the studied area which mainly collected from Hormozgan province seashores. Cap forms, number and form of rays, form of corona, hair scars and size of vegetative and reproductive parts of each species were studied after decalcification and results were presented in this paper.

In plants, there are complex network of transport, chelation, and sequestration processes that functions in maintaining concentrations of essential metal ions in different cellular compartments, thus minimizing the damage caused by entry of non-essential metal ions into the cytosol. In the presence of toxic ones, arbuscular mycorrhizal (AM) fungi are able to alleviate metal toxicity in the plant. In this study the effect of an arbuscular mycorrhizal fungiFunneliformis intraradices on growth, Nickel tolerance, and ABC transporter and metallothionein expression in leaves and roots of tall fescue (Festuca arundinacea) plants cultivated in Ni polluted soil were evaluated. The fungi infected (M+) and uninfected (M-) fescue plants were cultivated in soil under different Ni concentrations (0, 30, 90 and 180 ppm) for 3 months. Results demonstrated the positive effect of fungi colonization on the increase in growth and reduction in Ni uptake (90 and 180 ppm) and Ni translocation from roots to shoot of tall fescue under Ni stress. The results also demonstrated that the level of ABC transporter and metallothionein transcripts accumulation in roots was considerably higher for both M- and M+plants compared to the control. Also, M+plants showed less ABC and MET expression compared to the M- plants. These results demonstrated the importance of mycorrhizal colonization of F. intraradices in reduction of Ni transport from root to shoot of tall fescue which alleviates Ni-induced stress.

Pear (Pyrus sp.) is an important fruit growing in temperate and cold areas that due to suave and high economic value were cultured since ancient in Iran. The purpose of this study was to identify the best media for fast propagation of healthy plants of Pyrus sp. using tissue culture technique. At first, the pears samples were collected from the garden of Astan Quds Razavi and lateral and terminal buds were used as explants. For sterilization 0.1% mercuric chloride for 3 minutes, 70% ethanol for 1 minute was the best treatment. A Complete Randomized Design experiment was carried out with 3 replications. Results showed that Regeneration initiated on MS basal medium supplemented with 3 mg/l BAP+0.01 mg/l IBA. The most multiplication was on MS medium supplemented with 0.1 mg/l IBA+3 mg/l BAP. The highest shoot length was observed in MS medium supplemented with 0.01 mg/l IBA+3 mg/l BAP. The results of ANOVA showed no significant differences between rooting treatment. The rooted plantlets transferred to Jf pot for adaptation and then transferred to soil.

In this study, the relationship between altitude, climate and soil characteristics as important and effective factors on the growth characteristics, seed germination and essential oils of Ziziphora clinopodioides were examined. Three habitats of this species with different altitudes were selected in Alborz and Mazandaran provinces. Growth characteristics of Z. clinopodioides bushes in 45 plots located at the three habitats were recorded. Seed of this species collected from three habitats and their viability was determined. Three soil samples were taken from each habitat and some physical and chemical characteristics were measured. Analysis variance results of data showed that there is a significant difference among the three habitats from the viewpoint of growth characteristics, soil features and common combinations of essential oils. The highest seed viability was obtained for Rineh habitat with chilling and scratching seed coat. The most important environmental factors affecting the vegetative characteristics and essential combinations was determined using principal component analysis. The results showed that annual temperature, absolute minimum temperature, maximum temperature of the warmest month, number of frost days, altitude, electrical conductivity, moisture saturation, organic matter and soil texture had the greatest impact on these properties.