نشریه فیزیولوژی محیطی گیاهی
پیاپی 8 (زمستان 1386)

The seeds extract of Silybum marianum (L.) Gaertn is named silymarin and used in treatment of liver diseases, diabetes (II) and hypercholesterolemia. There are different solvents (methanol, ethanol, acetonitrile and acetone) for extraction of this compound. Water is an inetersting alternative because of its low operating and disposal costs. This study was undertaken to evaluate the efficiency of different methods on silymarin production and followed by HPLC analysis of extracted flavonolignans. The highest content of taxifolin, silychristin and silydianin were 0.63, 0.9 and 2.35 mg g-1 DW, respectively in a soxhlet extraction with water for 12 h after a pre-treatment step involving defatting with petroleum ether. The highest content of silybin and isosilybin were extracted 0.24 and 0.15 mg g-1 DW in a soxhlet extraction with water without defatting process. Although the ratio of the extracted componds with water were less than methanolic extraction, for increasing the quality of the products, the water extraction steps should be well studied both in terms of time and methods.

Medicinal herbs have been used to promote health for centuries, and have increased in popularity and sales in the last 10-20 years. Pot marigold (Calendula officinalis L.) is a medicinal herb whose dried flower heads are used to heal wounds. In order to understand the effects of sowing dates and plant density on grain and flower yield of pot marigold, an experiment was conducted at Agricultural Research Center of Islamic Azad University, Birjand Branch in 2005. Three sowing dates (30 March, 14 April and 30 April) and three plant densities (plant distances on row were 10, 20 and 30 centimeters) were compared in a split- plot design based on randomized complete blocks with 3 replications. Seed and flower yield were significantly different at planting dates and plant densities. Sowing date had significant effects on flower and seed harvest index. The latest sowing date had the highest flower and seed harvest index. Plant density did not have any significant effect on flower harvest index, but the effect on seed harvest index, was significant. In total, the result showed that the first sowing date with 25plants/m2 had the highest grain and flower yield.

Allelopathy is phenomenone that some of the plant species relase special chemical compounds and by this way inhibit germination and growth in other plants.Today using of allelopathic potential in plant is considering  in order to control of weeds growth. It is said that allelochemical compounds may in lower concentrations cause stimulate of growth and in higher concentrations inhibit it.In this research effect of different concentrations of aqueous extract of canola (0,10,20,40,60,80%) on germination percentage, growth parameters and peroxidase, catalase and polyphenol oxidase activity in Phallaris minor seedling was evaluated. Results this research showed that canola extract in higher concentrations decreased germination percentage, length, fresh and dry weight in radicle and hypocotyl of Phallaris.Also activity of antioxidant enzymes as peroxidase and catalase in higher concentrations of extract decreased.Only in 20% concentration of canola extract germination ,fresh weight of radicle, hypocotyl length and dry weight hypocotyl in Phallaris increased.

Copper is one of the heavy toxic metals that its toxicity is currently under investigation, in different plant types considering physiologic, biological, molecular, cellular and genetic aspects. In this research the copper toxicity effect on some of physiological activity of "Brassica napus L." Hylo 401 and RGS has been student. Seed of Brassica were cultured in hydroponic environmental. Roots and shoots used for evaluation of different treatments: Cu (5, 15, 25μm/l), Cu & AsA (0.5μm/l), Cu & GA3 (0.05μm/l) and Cu, AsA & Ga3 (as above), experiments were done in three replications in each treat group. In both Hyola 401 and RGS following factors were decreased significantly (p<0.05); germination percent, unsoluble sugar, K+ ions (in shoot and root). In both Hyola and RGS following factors were increased significantly (P<0.05) soluble sugar, proline. The finding of the study suggest that upon copper stress, in majority of studied parameters, Hyola 401 was more resistant than RGS. AsA treatment accompanying Cu, attenuated Cu effects on Brassica seedling, however GA3 exaggerated the Cu effects. Collected data were exracted and statistical analysis with SPSS statistical software 14th edition, performed. The results suggest that Cu induces inhibitory effects on growth and some of physiologic activities of plnant.

The compostion of the oils from flower and leaf of Achillea wilhelmsii C. Koch were collected during the flowering priod from 15 km away from Esfhan on alt. 1650 m. in July 2003. The essential oils were obtained by different methods of distillation (steam distillation and hydrodistillation), the percentage of oils for flower were 0/17% and 0.25% respectively, and calculated on the dry weight, and analysis by GC and GC/MS. The major constituents determined by hydrodistillation method in flower were p–cymene (33.3%), terpinolene (11.2%) and a-thujene (10.9%) and by steam distillation method in flower were p – cymene (22.1%), germacrene B (11%) and terpinolene (9.8%), respectively.

Darkesh area is located in northern Khorassan province and west of Bojnurd. This region is located between longitudes 56o41' to 56o49'W and latitudes 37o27' to 37o27'N. Its maximum altitude is 2455m. The regional climate is cold mountains and subhumid, and the precipitation in this region is about 502mm. Based on floristic studies, more than 506 species, 310 genera and 76 families were determinated. Also, more than 140 species with medicinal value were collected. The families of Lamiaceae (with 26 species), Asteraceae (with 21 species) and Rosaceae (with 13 species) have higher contribution in this region. The biological forms in this region are follow: 40% Hemicryptophytes, 18/4% Therophytes, 14/25% Geophytes, 13/57% Phanerophytes and 6/42% Chamaphytes. The phytogeographical distribution of species belong to Irano-Touranian, Euro-Siberian and Mediterranean.

In this survey flora of Deh Zaman iron mine region in Bardascan. has been studied. The method of plant collection in this region was classical method of plant taxonomic studies. Collected plants were recognized and determined families, genera and species of them by using of indispensable references. Alphabetically list of taxa in this region was provided on the base of families and scientific name. Collected plants are transmited to Herbarium of Reserch Center for plant Sciences in Ferdowsi university of Mashhad. The life form of plant species was determined by using of Raunkiaer’s method. The plants of Deh Zaman iron mine region are including 29 families, 75 genera and 95 species the more species belong to Asteraceae with 12 species. Life forms of plants of Deh Zaman iron mine region are including: 68.42% therophyte and 12.63% hemicryptophyte, 8.42% geophyte, 5.26% chamephyte and 5.26% phanerophyte.

Salinity stress is a serious threat of plant growth and production all over the world. Salinity in comparison with other stresses, limits the plant growth in a wider scale. So there is a possibility of cultivar diversity use in a desirable traits selection under stress conditions. Therefore, to identify selection indices in hull-less barley under salinity stress. This experiment was conducted. This experiment was investigated in 2004-2005 in green house at Golestan agricultural research center. The design of the experiment was random complete block design (RCBD) with 4 replications in a large plat (5×4×1.8m3). 30 centimeters between row on a single line 1.5m.For irrigation using level of salinity 160 mM NaCl. results of variance analysis showed that traits of relative water content (RWC), height, tillage in shrub, number of fertile tiller, length of spike, number of grain in spike, as significant different for  traits and most of them decreased under stress conditions. But the hieghst decrease was observed in grain yield, biologic yield, plant height and leaf area index.