Iranian Journal of Plant Physiology
Volume:2 Issue: 4, Summer 2012

The effects of salinity on growth, leaf area and water relations of two grape genotypes (Gharashani and Shirazi) were studied under 2-week salinity (25, 50 and 100 mM NaCl). Growth and fresh weights of all plant parts were significantly (p

As organisms exposed to various abiotic and biotic environmental impacts, plants are able to recognize and respond to their surrounding environment with high specificity. Electromagnetic field radiation is an important effective stress factor on growth and development of plants. Our research focused on plants grown from wet pretreated seeds with low frequency electromagnetic field exposure comparing them with the control. Three replicates were used in the experiment with 30 seeds in each sample. The treatment wet seeds, were spread on the moist filter paper in Petri dishes before they were placed between parallel coils of electromagnetic radiation generator and were exposed by a magnitude of 1mT, for 2hr. Control seeds were placed between coils under similar conditions but not connected to the power. Morphological comparison of the treated and control samples showed that the percentage of seed germination and average root length of the treatment plants increased, but the difference in root length was not significant. A significant decrease in the mean shoot length, leaf area, and fresh and dry weight was observed. Also, electromagnetic radiation exposure caused significant decrease in the rate of Chlorophylla and chlorophyll b. However, carotenoid and activity of non-enzymatic antioxidant content in treatment samples significantly increased in comparison with control plants.

Asparaginase was extracted from plant parts of Pisum sativum subspp. Jof collected from a field crop. Asparaginase activity was detected in seeds, stems and leaves extracts. Enzyme activity was higher in seeds extracts (30.0 U/ml) compared with leaves extracts (26.4 U/ml) and stems extracts (16.1 U/ml), respectively. Optimum conditions for the activity of crude asparaginase extracted from plants seeds were studied. Results showed maximum activity of asparaginase was achieved when the enzyme was incubated with 200 mM of asparagines in a ratio of 1:3 (V/V) at 37 °C for 30 minutes in the presence of 0.05 M of potassium phosphate buffer solution at pH 8. Asparaginase activity was equal to 602.6 U/ml under optimum conditions.

Rosa canina L. is a member of Rosaceae family, which is well-known for its high phenolic contents. These compounds are known to possess antioxidant and antiradical effects. In order to compare the antioxidant and antiradical activity of wild Rosa phenolic extracts, two wild Rosa species (Rosa canina L. and Rosa pimpinellifolia L.) were selected from Takab, Oshnavieh and Qasemloo Valley of Urmia, West Azerbaijan province, Iran, in 2011. The fruits of R. canina and R. pimpinellifolia were collected and then methanolic extracts were prepared from these fruits. The extract's total phenolic and flavonoid contents and scavenging capacity for radicals nitric oxide, hydrogen peroxide, and DPPH were analyzed. Fruit extracts, respectively, had a range of 176.48 ± 2.71 and 225.65 ± 2.50 mg gallic acid equivalents /100 g methanolic extract in total phenolic content, 0.41± 0.02 and 2.02 ± 0.03 mg quercetin/100 g methanolic extract in total flavonoid content, 22.41 ± 0.64% and 58.10 ± 0.72% in hydrogen peroxide, 79.16 ± 0.61% and 87.78 ± 0.10% in DPPH, and 76.93 ± 2.31% and 236.76 ± 16.04% in nitric oxide radical scavenging percentage. The findings suggested that radical scavenging capacities of R. canina and R. pimpinellifola extracts in different populations positively correlated with phenolic content.

Iron is a necessary mineral for plant's biological redox system and an important component of many enzymes. In the present study, effect of iron on morphological, biochemical, and physiological properties of soybean were investigated. The experiments were arranged in a completely randomized design with three replicates. Analysis of the data was carried out using SPSS with multiple range Duncan test (P

Achillea biebersteinii is a perennial herbaceous medicinal plant that belongs to Compositae family with useful properties, such as: anti-diaphoretic, antihemorrhagic, antiinflammation, antibiotic, antifungal and antioxidant effects. The objectives were; to determine the composition of essential oil components with the use of GC and GC/MS. Forty–two components were found and 98% of the identified oil constitunts categorized with above medicinal properties were; 1, 8 cineole (30.9%), cis-ascaridole (12.8%), alpha-terpinene (9.6%), alpha-terpineole(6.3%) and camphor (4.3%), with 37 minor extra components. Therefore, efforts have been directed to micro-propagation through in vitro culture with a view to producing secondary metabolites. So in this research, tissue culture has been optimized in four stages. At first seeds were sterilized then placed in different proportions of MS media. After 10 days the young seedlings emerged and after cutting their roots, were placed on MS media supplemented with different concentrations of BAP (2, 5, 10 mg/lit) in order to study its effects on Shoot induction. At 5 and 10 mg/lit both shoot and callus formed (with higher proportion at 5 mg/lit). At this stage, three characters of young seedlings have been analyzed: The number of leave/ the length of leave and the length of the tallest leave. In the third stage, young seedlings have been placed on MS media with no growth regulator. Then, the young seedlings were transferred to MS media supplemented with 2 mg/lit IBA. The best media for incubator use were MS media supplemented with 5 and 10 mg/lit of BAP.

Biological fertilizers are compounds comprising various free living microorganisms that are able to change the basic nutrients into available form through biological procedures. Being an important source of nutrients in sustainable agriculture, these fertilizers lead to better seed germination and development of root system. In order to investigate the effect of biological fertilizers on the medicinal plant, dill (Anethum graveolens), an experiment was conducted in completely randomized blocks with 3 replications using 4 treatments in Lueen plains in Saveh, central Iran. Treatments included nitroxin (Azospirillum and Azotobacter), Pseudomonas florescence containing phosphate solubilizing bacteria, mixture of nitroxin and Pseudomonas florescence fertilizers, and control (no fertilizer). Findings suggested that application of biological fertilizers significantly increased seeds performance, biological yield per plant, plant height, number of spikes per plant, number of seeds per spike, number of seeds per plant, and the weight of 1000 seeds. Among the treated plants, mixed treatment of nitroxin and Pseudomonas florescence caused maximum increase in most of the parameters under study. This was followed by nitroxin treatment which resulted in the second most pronounced difference with the control. The minimum and maximum seed performances were observed in mixed treatment of nitroxin and Pseudomonas florescence (16.31 g per plant) and control plants (9.8 g per plant), respectively. In general, results of the present study revealed that application of biological fertilizers plays a remarkable role in improving growth characteristics and yield compounds of Anethum graveolens and they can be viewed as a suitable replacement for chemical fertilizers.

Making an increase in the yield of agricultural plants including barely is considered as the main challenge for researchers in agriculture related sciences. Water-soluble carbohydrates transport and source–sink relations have a significant effect on the grain yield. This study was carried out in order to examine genotypic variation of storage and remobilization ability of carbohydrates in eighteen developed and two commercial varieties of barley. The study was arranged in a complete randomized block design with three replications. Samples were collected at anthesis and 14, 21, and 28 days after anthesis. Dry matter and length of peduncle and penultimate, and other physiologic and morphologic characters including leaf area index and SPAD number were examined in different stages after anthesis. At the maturity, grain yield and its components were measured. A positively significant correlation was observed between the dry matter of the last two internodes during grain filling and the rate of stem remobilization and grain yield. According to the findings, a high level of variability rate of stem remobilization was observed in different barley genotypes which can be used in barley breeding program.