مجله پژوهشهای گیاهی (زیست شناسی ایران)
سال سی و دوم شماره 4 (زمستان 1398)

Salinity is one of the most important abiotic stresses which with produce a reactive oxygen species affect on production and quality of herbal products. Plants are using antioxidant systems such as ascorbate peroxidase and guaiacol peroxidase to deal with different types of free radicals.Also, salinity stress, affect on chlorophyll content and causes ions to disrupt the homeostasis of sodium, potassium, chloride, and calcium. For this purpose, these parameters in spinach in resistance to salt stress were studied. In this study, Salinity at four levels( 0,200,400 and 600 Mm) in a period of 14 days after the stress and intermittent interval (72 hours)in a factorial and completely randomized experiments with the model of base design were considered. Ascorbate peroxidase and guaiacol peroxidase activities were measured using standard method. Also, Ions of sodium, potassium and chlorophyll and carotenoid content in the treatment of salinity stress were measured. Data obtained from this study using the statistical software SAS and MSTATC were analyzed. Our results indicated that the effect of salinity stress on the activity of anti-antioxidant enzymes, ascorbate peroxidase, and guaiacol peroxidase was significant. The results showed that with increasing salinity level, the sodium and potassium ions in leaf compare to control has been significantly increased and reduced, respectively. The concentration of chlorophyll and carotenoid pigments decreased with increasing salinity level.

Analysis of codon usage is very important to optimize the production of proteins in gene expression system. Gossypium spp. is the most important fiber crop in the modern world. In this research the complete nucleotide sequence of the chloroplast genomes of two wild cotton species was studied and analyzed using codon W software. Synonymous codon usage of 57 protein coding genes in chloroplast genome of G.thurberi and G.arboreum was analyzed to find out the possible factors contributing codon bias. All preferred synonymous codons were found to use A/T ending codons as chloroplast genomes are rich in AT. Correspondence analysis and method of effective number of codon as NC-plot were conducted to analyze synonymous codon usage. ENC Vs GC3 plot grouped majority of the analyzed genes on or just below the left side of the expected GC3 curve indicating the influence of base compositional constraints in regulating codon usage. According to the corresponding analysis, codon bias in the chloroplast genome of G.thurberi and G.arboreum are related to their gene length, mutation bias, gene hydropathic level of each protein, gene function and selection or gene expression only subtly affect codon usage. This study provided insights into the molecular evolution studies.

Peppermint (Mentha piperita L.), with numerous medicinal properties is one of the most important plants from Lamiaceae family. To investigate the effects of drought stress and salicylic acid on peppermint, an experiment was conducted as factorial based on completely randomized design with four replications in the greenhouse of Medicinal Plants Department, Faculty of Agriculture and Natural Resources, Arak University during 2017. Studied factors included drought stress (35%, 65%, 95% and 100% of field capacity) and salicylic acid (0, 50, 100 and 150 mg/l). Results showed that salicylic acid (concentration) improved most physiological traits including chlorophyll index, relative water content, chlorophyll a, b and total chlorophyll, carotenoids, phenol and flavonoid content, antioxidant capacity, ion leakage and malondialdehyde. The highest level of ionic leakage and malondialdehyde was obtained in combination treatments of 50 mg/L and 35% FC. Maximum total flavonoid content and antioxidant capacity were observed in the combination treatment of salicylic acid (150 mg/L) and 95% drought stress. Therefore, application of this growth regulator at the level of 100 mg/L can be helpful in alleviating drought stress in peppermint.

Loranthus grewinkii is a damaging species that is a type of leafy species and inhabits on trees of Zagros forests. This plant in order to provide some of the needed nutrient elements for photosynthesis, it needs its host plant to obtain the water and nutrients. For that reason, they cause changes in biochemical compositions in their host trees. In this research, the effect of Loranthus grewinkii Boiss & Buhse was investigated on organic compounds such as total tannin, total phenol, dense tannin, flavonoids, protein, total sugars, insoluble sugar and proline in Amygdalus Scoparia in Southern Zagros forests, Khoram Abad, Iran. The results showed that the total phenol, dense tannin, total tannin, flavonoids and proline in the leaf of the infected individuals were significantly higher than the healthy wild almond (P≤0.05 and P≤0.01). Also, the results showed that sugar content, soluble sugar and protein in healthy individuals were more than the infected individuals to Loranthus grewinkii (P≤0.05, P≤0.01). It is seemed, increasing secondary compounds such as total phenol, dense tannin, total tannin, flavonoid, and proline due to disease occurs in tree to make efforts in orderto increase tolerance to the disease. Therefore, due to the activity of the semi-parasitic plant on these trees, the drying phenomenon is observed on the crown or branches of wild almond trees, so it can be used in the cleaning practice to prevent the prevalence and spread of Loranthus grewinkii in the Southern Zagros region, especially, Lorestan province.

Functional groups are defined as groups of species exhibiting similar responses to an environmental variables. The aim of this study was to investigate the response of plant functional groups to some environmental variables in Mountain forests of southern Zagros (Khuzsetan province- county baghmalek). Vegetation and environmental factors were sampled by 50 circular plots of 1000 m2 selective-randomly along an elevational gradient from 646 to 3172 m a.s.l. sampled vegetation were identified in terms of different growth Forms to woody (tree and shrub), herb and woody seedling (tree and shrub seedling) functional groups and the changes of these functional groups in relation to environmental variables were analyzed using Canonical Correspondence analysis. The results showed that all the functional groups of forest vegetation showed a statistically strong significant correlation with elevation, soil Electrical conductivity, soil available k and soil pH. Also woody functional group showed a correlation with Microbial biomass carbon, clay percentage, Aspect, Organic matter content, sand percentage, slope and Total of nitrogen, herbs showed a correlation with Soil organic matter, soil available p, Total of nitrogen, sand percentage, clay percentage, basal respiration, Bulk density and slope, while woody seedlings showed a correlation with aspect, Total of nitrogen, sand percentage, slope, Microbial biomass carbon and clay percentage. species diversity of woody functional group to 2350 m a.s.l were hight and then above 2350 m a.s.l were low. while herbs were lower diversity at intermediate elevations (1300-1600 m a.s.l) and above 2350 m a.s.l and seedlings had maximum diversity at intermediate elevations.

Cadmium is an unnecessary heavy metal with a relatively high mobility in the soil-root system and the potential for toxicity in plants and humans. This research investigates the effects of cadmium chloride and its interaction with methyl jasmonate on cadmium accumulation, its relative water content, proline content, the amount of photosynthetic pigments and the activity of superoxide dismutase and catalase in wheat seedlings (Sivand cultivar). The results showed that cadmium accumulation in root and shoot at 300 μM increased 30 and 17 times, respectively, compared to control level. Cadmium at concentrations of 200 and 300 μM resulted in significant changes in the studied traits. So that activity of catalase and superoxide dismutase enzymes is increased 2 to 3 times and the amount of proline is increased by 15%. While chlorophyll a, chlorophyll b and carotenoid content dropped by between 20% and 30% and relative water content was about 3% lower than the control level. Results showed that 10 μM methyl jasmonate spray on plants under cadmium stress increased the amount of proline (16%) and photosynthetic pigments (23%) and decreased the cadmium content of the root and shoot by 30%. At the 100 μM of methyl jasmonate the activity of catalase and superoxide dismutase enzymes increased by 2 and 3 times, respectively. The results of this study indicate the ability of methyl jasmonate in change of cadmium accumulation in the root and shoot and in increase the activity of antioxidant enzymes.

The aim of this study was to investigate the effect of different light intensity and ascorbic acid on the growth and flowering of Zinnia elegans L. The experiment was laid out as split plot based on a completely randomized design with three replications. The main factor was light intensity with three levels (600, 1200 and 1800 μmol m-2 s-1) using shade net and sub-plot was weeky foliar spray of ascorbic acid with three concentrations (0, 1, 2 mM). Results showed that as light intensity decreased, plant height, leaf area and spatial leaf area and flower diameter were increased and root length and volume, fresh and dry weight of leaf, stem and root, stem diameter, leaf number, electrolyte leakage and malondialdehyde increased. Flower diameter and flower fresh and dry weight, were higher in plants grown under 1200 μmol m-2 s-1 light intensity compared with those in 600 and 1800 μmol m-2 s-1. Also, with decreasing light intensity, flowering delayed, while, flower longevity increased. Moreover application of AsA increased plant height, root length, leaf fresh and dry weight and electrolyte leakage and reduced leaf area, root volume, stem fresh and dry weight, root dry weight, time of full flower opening and flower diameter. Overall, the results of this study showed that Z. elegans could be grown under full sunlight conditions, however, its growth and flowering quality were higher under 1200 μmol m-2 s-1. Therefore, it is possible to grow it under semi-shading conditions.

Mentha pulegium is an aromatic plant in the Lamiaceae family. Plants of this family estimated to contain 200 genera with over 4,000 species. M. pulegium is an aromatic plant with high industrial and commercial values.In this study, morphological and anatomical analysis of the trichomes on leaves, sepals, and petals of M. pulegium were carried out using light microscopy and scanning microscopy. The essential oils were obtained using hydrodistillation method and analyzed by Gas Chromatography (GC) and Gas Chromatography Mass Spectrometry (GC/MS). Morphological investigation revealed that these species had three types of non-glandular trichomes and two types of glandular trichomes. Histochemical test demonstrated both of trichomes have a positive reaction to neutral lipids, pectin, alkaloid compounds, phenolic compounds, and terpenoids. The results of oil analysis in different development stages show the presence of several compounds. The composition analysis of the essential oils using GC and GC/MS in vegetative and flowering phases indicated that pulegone and menthone were the major compounds with more than 90% of total oil composition. In mentha pulegium, pulegone amount is reduced from 76.58% to 68.19% and menthone amount is increased from 19.94% to 25.40%.Regarding to the reduction of pulegone and menthone amount from 96.52% to 93.59% and also appearance of new chemical compounds in flowering phase and increasing in trichomes density at this phase, it can be concluded that the plant exchange some amount of energy to produce new compounds with special volatility and fragrance as well as changing the synthesis pathway in trichomes cells.

In the present study, transgenic tobacco (Nicotiana tabacum) plants over expressing P5CS gene under in vitro salt stress condition. Tobacco plants transferred to MS medium containing 100 and 200 mM NaCl, then foliar application of two glycine betaine concentrations, including 20 and 40 mg L-1 were applied on the surface of the plants with four to six leaves at University of Isfahan in 2015 with a completely randomized design with three replications. After 4 weeks post treatment results showed that, exogenous glycine betaine under salt stress increased fresh and dry weight, K+, content, leaf area, endogenous glycine betaine and soluble sugar. In contrast, the amount of photosynthetic pigments, proline, content, Na+ content, and Na+/K+ ratio were decreased. The results of this study showed that, exogenous application of glycine betaine in tobacco plants was effective in reducing the negative effects of salt stress and improved growth parameters. However preliminary experiments showed a decrease of proline and increase of endogenous glycine betaine in stressed platns. On the other hand, results indicated that, communion cooperation of these osmolytes to cope with stress conditions has possibly been occurred. According to the results of this study, that cooperative roles of glycine betaine and proline in membrane stability and reducing the negative effects of salinity in both transgenic and non-transgenic plants it can be suggested.

Understanding the role of plant species in plant composition is very important in the study of climate change processes, understanding the properties of ecosystems such as sustainability, flexibility and ecosystem assessment.The classification of plant species according to the Grime’s CSR strategies was studied in Haftadgholeh and Meyghan playa of Arak. Random- Systematic design was applied to sampling, and the characteristics of plant species were recorded according to Hodgson et al., 1999 method. A total number of 172 vascular plant taxa belonging to 46 families and 136 genera were studied. The life form spectrum, based on Raunkiaer system, revealed that Hemicryptophytes and Therophytes have been the most dominant life forms. The floristic composition of the area is strongly influenced by large number of Irano-Turanian elements.The most important strategies were competitive-ruderal (CR) (36.5%), competitive-stress tolerant (CS) (18.8%) and competitive/competitive-ruderal (C/CR) (12.9%). Few species (4 species, especially tree and shrub species present in less intact areas of Haftadgholeh), exhibited a purely competitive (C) strategy. It seems that livestock grazing and stress caused by soil salinity, altitude and drought, increase the frequency of competitive- ruderal group strategies such as CR, C / CR, R / CR and CR / CSR and SC, C/SC, S/SC, SC/CSR, SR and SR/CSR, respectively. The data generated in this research can be the basis for using the CSR classification model to determine the response of plant species to the pattern of environmental factors change, disturbance as well as the evaluation of managed ecosystems.

Air pollutants are one of the most important environmental problems in the world. Trees and shrubs are the most important agents to reduce air pollutants, which through various mechanisms can respond to the destructive effects of air pollutants. In current study, the resistance of Acer velutinum Bioss. to air pollutants like carbon monoxide, nitrogen dioxide and ozone contaminants through some physiological parameters such as photosynthetic pigment, anthocyanin, total protein, total phenol and mineral elements such as nitrogen and phosphorus were evaluated. Soil parameters and climate factors were also measured. A. velutinum was collected in three areas in Tehran including Tajrish, Laleh Park, Shahr Park and one area in Mazandaran including Chaloos. Acidity, electrical conductivity and temperature has been hardly changed in any areas. The results indicated that the content of air pollutants in in three areas of Tehran was higher than Chaloos. Likewise, the rainfall and relative humidity have also decreased in different parts of Tehran which can be considered as the consequences of increasing air pollutants. The results showed that the content of chlorophyll a, b and carotenoids, protein, phosphorus and anthocyanin in plant grown in three areas of Tehran with higher content of air pollutants were higher than those in plant grown in Chaloos. In deed, physiological resposes of Acer indicates its resistance to above-mentioned air pollutants.

Scropholaria striata Boiss (.Scropholaria striata Boiss) is the name of the thirsty place of the most important herbs in the family of mummies. In Iran, the plant grows more in cold and mountainous regions of Zagros. Although the chemical composition of this plant has not been identified, the people living in the province of Ilam have been experimenting experimentally for the treatment of various diseases. The present study was carried out to analyze the effect of the region (climate) on the antioxidant activity and phenol content of this plant. For this purpose, three areas of Badreh, Darehshahr and Dehloran in the same direction (northeast) with a distance of 100 meters, the fruit-bearing branch of the plant were collected in June 1395 and coincided with the emergence of fruit. Antioxidant activity of methanolic extract of plant samples was measured by DPPH method and total amount of phenolic compounds was measured by Folin Seokalto method. After statistical analysis, the results indicated that the effect of the region on extract yield, total antioxidant capacity and total phenol was significant at 1% probability level. The highest efficacy (19.37 ± 3.7%), antioxidant activity (126.556 ± 0.96 μg / ml) and total phenol (55.76 ± 3.717 ± 55 μg / ml) In the Valley of Shahr region. So, climate change can cause some secondary compounds to be synthesized.

In order to investigate the effect of organic and inorganic fertilizers on yield and concentration of elements in Hashemi cultivar of rice, a randomized complete block design with three replications was conducted in a field experiment in Rice Research Institute of Iran. Fertilizer treatments included chemical fertilizer, poultry manure and control. The measured traits included grain yield, straw and chaff, biomass, nitrogen, phosphorus, potassium, iron, copper, zinc, conversion efficiency and grain quality. The results showed that fertilizer treatment had a significant effect on all measured traits. The highest grain yield (6629 kg ha-1) was obtained from chemical fertilizer. The highest straw yield was 5974 kg ha-1 from poultry manure. However, the grain yield and straw yield was not significantly different between chicken manure and chemical fertilizer treatment. The highest amounts of nitrogen, phosphorus, potassium, iron and copper were obtained in seed using chemical fertilizer, which did not have significant difference with chicken manure. The highest zinc content was found in chicken manure treatment. In general, although the traits mostly in the chemical fertilizer treatment were higher than poultry manure treatment, the differences were not significantly different. Therefore, poultry manure can be used as a safe alternative to the environment or as a safe supplement to chemical fertilizer in rice farming.

Proline is a common compatible osmolyte and, by osmotic regulation and protecting membranes, proteins and enzymes, protects plants towards destructive effects of osmotic stresses. Brassinosteroids are a new group of plant growth regulators and stimulate their growth. The effects of foliar spraying of proline and 24-epibrassinolide on growth indices and biochemical characteristics of summer savory (Satureja hortensis L.) were investigated in this study in greenhouse conditions. Foliar treatments including control (no spraying), proline (20 mM) and 24-epibrassinolide (1 μM) were performed in both vegetative and reproductive stages. According to the results, foliar proline led to increasing plant prolin content to 394.4%, chlorophyll index to 4.8%, total phenol to 9.8%, flavonoids to 18%, yield of essential oil to 15.8%, fresh weight of aerial parts to 8%, dry weight of aerial parts to 7.8%, fresh weight of leaf and flower to 6.8%, dry weight of leaf and flower to 8% and stem diameter to 7.4% compared to the control. In addition, 24-epibrassinolide spraying caused a significant increase in phenolic compounds (32.15%) and internode length (8.3%) of the plant in coparision to control.

This research was performed to investigate effect of growth facilitators on growth and functional characteristics of Onobrychis sativa Lam. in a factorial structure with a completely randomized design in greenhouse. Growth facilitators included potassium Nano‐silicate (0, 500 and 1000 mg/l), hydrogel of Boloorab (0, 10 and 30 g/kg), EM (0, 1 and 2%) and animal manure (0, 100 and 200 g/kg). At the end of growth, to investigate effect of growth facilitators on growth of O. sativa were measured fresh and dry weight of aerial organs and root, root length, plant height, volume root, aerial organs volume, establishment percentage, leaf area, photosynthesis rate, chlorophyll index, leaf relative water content, electrolyte leakage and curtain stability index. The results showed that the highest amount of dry weight (27.89 g/pot), root length (28.78 cm), plant height (70.70 cm), root volume (7.10 cm3), aerial organ volume (23.50 cm3), establishment percentage (70.80%), leaf area (4359.92 cm2/pot), photosynthesis rate (14.19 μmol/m2 s) and chlorophyll index (7.9) was observed in the treatment of animal manure 200 mg/kg. Other treatments also had desirable effects on growth and functional characteristics of O. sativa. Therefore, these treatments can be used in rangelands improvement and reclamation projects, and the conversion of abandoned dry farming lands and low-yield dry farming lands to pasturelands for the forage production.

Plants have a variety of defense mechanisms, which are often induced after herbivores attacks. Induced defense mechanism has advantages for plants by reducing the performance or preference of herbivores toward host plants such as aphids, which later attack the plant. In current research, in first stage, four safflower cultivars including, Sofeh, Goldasht, Faraman, Mahali-Isfahan and a wild safflower species, Carthamus oxyacantha, were exanimate feeding of Helicoverpa armigera (Lep.: Noctuidae) larvae. Then all larvae were removed and these plants were maintained uninfected for 72 h. In second stage, four unwinged adult of safflower aphid, Uroleucon carthami (Hem.: Aphididae) were placed on both infested and control plants. Then they were reared for 15 days. The results showed that cotton bollworm larval feeding on safflower, as an induced resistance element, had a significant on plant physiological indices and aphid reproduction. Indicators such as H2O2, prolin, protein content and reducing sugars were significantly affected by the biotic stress of the larva compared to the control. These changes indicate that the responses of different safflower varieties to larvae was not the same and cultivars like Mahali-Isfahan showed better compatibility for induced resistance and accumulation of important metabolites such as oxygenated water, prolin, sugar and protein.

Allicin as the best-known active compound of garlic (Allium sativum) has a vast variety of biological effects.
The effect of iron sulfate was evaluated on allicin, cysteine, growth and protein contents of Allium sativum explants.
Garlic bulbs were surface-sterilized and cultured on Murashige and Skoog (MS) medium for 1 month then transferred to the medium supplemented with different concentrations of iron sulfate for 10 and 20 day periods. At the end, shoot and root samples were gathered and fresh weighted and length of plantlets measured. Allicin content was determined by HPLC method, cysteine and total protein contents were determined by spectrophotometry.
The highest amount of allicin and protein was observed for 11.12 mg/L treatment of root and shoot at both endpoints. The maximum content of allicin and protein were determined respectively on the root (16.62 mM/g FW) and shoot (8 mg/g FW) of 11.12 mg/L-treated explants after 20 days. On 5.56 mg/L-treated explants, a significant increase of fresh weight and length of root and cysteine content were observed in comparison with other treatments.
In addition, on the shoot of 1.39 mg/L-treated explants, a significant difference in fresh weight and length were measured compared with the other treatments.
Because of the important role of allicin on medicinal features of Allium sativum, probably iron sulfate could be a good elicitor for the elevation of allicin content of garlic explants.

Here 840th species of genus Astragalus is recorded for flora of Iran. Astragalus globiceps Bunge, belonging to Astragalus section Alopecuroidei DC., is recognized in NE Iran, Khorassan Province. This species has already been recorded in Kazakhstan, Uzbekistan, Kirgizstan, Turkmenistan, Tadzhikistan and Afghanistan. The picture and distribution map are presented, together with a description on the basis of the mentioned specimen and previous descriptions.