فصلنامه زیست شناسی گیاهی ایران
سال هفتم شماره 1 (پیاپی 23، بهار 1394)

The Shimbar or Shirin Bahar region with an area of 53000 h is located in 45 km north east of Masjed Soleyman city، Andica town and north of Shahid Abaspour dam. The area belongs to the Zagrosian district of Irano-Turanian region. In three seasons، winter، spring and summer of 2012 to 2013، herbarium specimens of the area were collected and named by the Floras of Iran and neighboring countries. In this research، 189 species belonged to 149 genera and 51 families were determined. Most of the species belonged to Asteraceae with 23، Poaceae with 19، Lamiaceae and Papilionaceae with 18، Rosaceae with 10، Apiaceae with 9 and، Brassicaceae followed by the Caryophyllaceae each with 8 species. The life forms of the species in Shimbar included 13% phanerophytes، 6% chamephytes، 25% hemicryptophytes، 15% cryptophytes and 41% therophytes. The highest precent of the species belonged to the Irano-Turanian region.

In this study، Lycopersicon peruvianum line 815 was grown on MS medium containing 0، 60، 90 and 120 mM NaCl. After 4 weeks of NaCl treatment dry and fresh weights، chlorophyll a، b، total chlorophyll and caretenoid، proline، sodium and potassium،، the total protein، SDS-PAGE pattern were studied. The results showed that dry and fresh weight in shoot and root decreased with increasing of NaCl concentration. Chlorophyll and carotenoid pigments did not show any significant difference between the control and the treated explants. Proline and sodium contents increased with salinity compared to the control، but the potassium level and total protein content decreased. K+/Na+ ratio decreased with increasing of salt stress. In addition، SDS-PAGE results showed different protein pattern between the treated and the untreated plants. According to the mentioned results salt stress could directly affect plant growth and it had indirect on metabolism of plant.

Soybean (Glycine max)، one of the most important agronomic crops in the world، is considered as a rich source of oil and protein production and much effort has been directed towards its genetic improvements using conventional breeding techniques، as well as molecular genetic approaches. Meanwhile، optimization of transformation of soybean requires an efficient system for production of stable transgenic lines. In this study، we reported the first attempt to use the cotyledonary node derived from mature seed for Agrobacterium mediate plant transformation in Iran. Surface-sterilized soybean seeds of DPX and Gorgan3 cultivars were soaked in distilled water overnight and used for explant production. The explants were inoculated in Agrobacterium tumefaciense (LBA4404) containing pBI121 solution. Positive transgenic plants which remained green in the presence of kanamycin، as a selectable marker، were used for the GUS assay. PCR، sequencing and the GUS assay showed successful expression of the GUS gene in the regenerated plants in both cultivars. Simplicity and efficiency were the main advantages of using the half-seed method which can be used to introduce useful and/or novel gene (s) into soybean.

Taxus baccata L. is the main and almost the sole source of paclitaxel، which is an anti neoplastic agent and is used as a cure for treatment of breast and ovary cancer. Since production of this drug is almost a destructive process and yew is an endangered plant، it is required to optimize its tissue culture and micropropagation system. In order to produce embryo derived callus 16 combinations of two plant growth regulators; 2،4-D (0، 0. 5، 1 and 1. 5 mg/L) and Kinetin (0، 0. 1، 0. 5 and 1 mg/L) were used to study its effects on callus formation and growth in Taxus baccata. It was determined that 1. 5 mg/L 2،4-D + 0. 1 mg/L kinetin was the best combination for callus growth. Increasing 2،4-D concentration، however، promoted callogenesis while kinetin only in a narrow range had positive effect on callus initiation.

Spearmint (Mentha spicata L.) is an important economical and medicinal plant from Lamiaceae family، which has gained research attraction as a model for biosynthesis of essential oils due to its high capability for synthesis of monoterpenes. Limonene is a simple monoterpene and its biosynthesis is catalyzed by limonene synthase; a key regulatory enzyme in the biosynthesis pathway of monoterpenes in spearmint plant. This study was concerned with the effect of colonization of roots with Funneliformis mosseae and F. etunicatum fungi on spearmint plant growth indices، leaf essential oils and changes in the expression of limonene synthase (LS) gene. This study also explained the application of GADPH gene as the internal standard for real-time quantitative PCR (RTqPCR) analysis of LS in spearmints. Our results showed that essential oil content of leaf in spearmint genotype Meybod inoculated with F. etunicatum was higher than that of genotypes from populations Kashan and Bojnourd and was 130% higher than the control. According to the results of this study، increase in transcript accumulation of the LS gene in leaves of spearmint plants inoculated with F. etunicatum was concordant with the increased essential oil contents and was dependent on the plant genotype.

In this study، the role of boron (BO33-) on improving tolerance of coriander plant (Coriandrum sativum L.) subjected to different concentrations of aluminum (Al3+) was evaluated. In this regard، an experiment was implemented with seven different concentrations of aluminum including: 0. 25، 0. 50، 1. 00، 2. 00، 3. 00 and 4. 00 mg/L Al3+ and three concentrations of boron including: 0. 25، 0. 5 and 0. 75 mg/L BO33- with the control treatment. The experiment was concluded based on completely randomized design with three replications. Seeds of coriander were germinated in germinator and seedlings were grown in Hogland´s solution with different boron and aluminium concentrations. Results showed that different levels of Al3+، decreased dry weight، leaf area، length of shoot and root، amount of chlorophyll and aluminium، while proline concentration and Al3+accumulation increased. Nearly، in all concentrations of Al3+، plant height، dry weight and chlorophyll content promoted with increasing boron concentrations، but proline concentration was decreased. It could be concluded that application of boron along with Al3+، might have proved plant growth and neutralized effects of Al toxicity.

microRNAs (miRNAs) are noncoding small RNAs that generally function as posttranscriptional negative regulators. The miRNAs play a direct role in plant responses to many types of environmental stresses. For example miR399 had a role in response to Pi deficiency. The aim of this study was to investigate the role of miR399 and sucrose in some physiological responses of Arabidopsis thaliana plants to phosphate deficiency. Therefore، miR399-overexpressing transgenic and wild type Arabidopsis plants were used. The plant seeds were cultured on the Suc+Pi+ (S+P+)، Suc-Pi+ (S-P+)، Suc+Pi- (S+P-) and Suc-Pi- (S-P-) media. Pi+ and Pi- refer to 1. 2 mM and 10 µM Pi، respectively and Suc+ or Suc- are media culture with 1% sucrose or without. The results showed that sucrose and miR399 had a dramatic effect on root architecture so that primary root length and its branches on S-P+ medium were significantly reduced in over expressed as compared with wild type plants. The highest anthocyanin and starch accumulation was achieved in S+P- media in both plant types. However، miR399 over expression was resulted in significant rise in anthocyanin accumulation on S-P- medium in transgenic relative to wild type plants. In addition، miR399 was resulted in significant rise in free phosphorous level in all types'' media. compared to wild type. These results were probably due to the role of sucrose and miR399 in signalling pathway during phosphate starvation in Arabidopsis plant.