مجله پژوهشهای گیاهی (زیست شناسی ایران)
سال سی‌ام شماره 1 (بهار 1396)

Species diversity measurement is an important key to conserve, monitor and evaluate vegetation as well as choosing the appropriate management strategies. Although managers seek for a rapid technique to assess the biodiversity, meanwhile, precision, accuracy and easy to use of plots are important criteria for measuring species diversity. To achieve these goals three plots, i.e. modified Whittaker plot, intensive modified Whittaker plot and C plot were evaluated to choose the appropriate size and number of plots to evaluate species diversity. In this study, the former is the newest version of the modified Whittaker plot that is being applicable with the latter for the first time in Iran and another important point that the emphasis should be put on it is that the outcomes of C plot are introduced for the first time in the world. Karsanak Rangeland was chosen two grazing intensities of light and medium and two slope aspects of the eastern and western including the four treatments of light–eastern, light-western, heavy-eastern and heavy-western. Each plot in three replicates per treatment was allotted as random systematic sampling. After collecting vegetation data, indices of diversity, richness and evenness of species were calculated using the software Past. Comparison of species diversity in different treatments was performed using ANOVA on SPSS software and graphs were plotted using Excel software.

Aluminum is one of the metals that showed toxic effects on various plants. Decreasing of pH in the soil will cause to solve Al ions, and absorbed by the roots of the plants; thus it can influence the growth of the plant. In this research, the toxic impact of aluminum on some physiological functions of the bean plants (Phaseolus vulgaris L.) is studied. Bean seeds were germinated on the wet papers and cultured in the hydroponics environment, and then treated by various aluminum concentrations (30, 40 and 50 millimolar). Results showed that aluminum cause to decrease of germination, length of the root and stem and insoluble sugars in the root of the treated plants under 10 and 20 days. The activity of catalase and peroxidase, and the amounts of soluble sugars and total proteins were increased in the roots of the aluminum-treated plants. The later one can be related to production of detoxifying proteins that were reported in some prior reports.

Plants are beneficial or harmful on other plants through allelochemicals which may be directly or indirectly released from alive, dead plants and or microorganisms. The aim of this study was to investigate the allelopathic effect of leaf extract from Eucalyptus on total protein content, enzymatic and non-enzymatic antioxidant activities of soybean (Glycine max L.) and velvetleaf (Abutilion theophrasti Medicus). Treatments were leaf extracts of Eucalyptus (25%, 50%, 75%, 100% w/v) and distilled water as a control. The results of pot culture experiments showed that the extracts decreased total protein content of both plants. In spite it was increased the proline content, phenolic compounds and activities of polyphenol oxidase and peroxidase of leaves. However the level of changes was different for examined plants. Sum of data showed that the allelopathic effect of Eucalyptus extract on velvetleaf was more than soybean and the concentration 75% and 100% of extract could be more analyzed as natural herbicide.

An experiment was condacted To study the allelopathic effect of saffron genotyps on bindweed in the department of agronomy and plant breeding of Isfahan University of Technology, Iran in 2012-2013. Experiment was arrange as a factorial in a completely randomized desiggn with three replication. Factors included 20 saffron genotypes obtained from different regions in Iran, ( Hamedan, Nishapur1, Nishapur2, Nishapur3, Nishapur4, Sabzevar, Mashhad1, Mashhad2, Natanz, Khaf, Khorasan, Torbatejam, Kashan, Gonabad, Torbat heydaryeh, Birjand, Yazd, Shiraz, Isfahan, Kashmar) and Aquous extracts were prepared from aerial parts of these saffron genotypes in concentrations of 0, 3, 6, 12.5, 25, 50 and 100%. Seedling traits of the attributes of Bindweed (as a target species) including radicle and plumule lengthes, radicale and plumule fresh weights, plumule dry weight, germination percent and velocity were measured.. Results showed that the effect of genotype and extract concentration and their interaction on measured traits were significant. Saffron genotypes had a different effect on the triats of bindweed. Genotypes "Khaf and Nishapur3" were proven to be the most allelopathic genotype, and genotypes "Kashan, Torbate jam and Gonabad" were found to leave minimal allelopatic effects on the target species. With increasing in aquous extracts concentration traits of target specie decreased, but the effect was diffreent. Maximum inhibition was observed in aquous extract concentrations of 100% and minimum inhibition was observed at aquous extract concentrations of 3% .

In plants, several protective systems cooperate to overcome stressful conditions such as the pollution of the medium to heavy metals. In this research, the influence of different concentrations of silver nitrate on growth index, chlorophyll content, H2O2 content, lipid peroxidation, proline content, and the activity of antioxidant enzymes in shoot culture of Artemisia annua L. were investigated. In order to show the effects of the silver as heavy metal, on the aforementioned indices, the experiment was carried out in a completely randomized design with 3 replications. The different concentrations of silver nitrate (0, 0.001, 0.01, 0.1, 1, and 2 mM) were added to liquid MS medium including Artemisia shoot. The results showed that the ratio "fresh weight/dry weight" of the treated samples in 0.1 mM concentration of silver nitrate was increased relative to the control. Chlorophyll a and b contents were increased in 0.001 mM concentration and chlorophyll a was decreased in 0.1 mM concentration in comparison to the control. Among the measured antioxidant enzymes activity, only catalase was increased in all concentrations. Silver nitrate elicitor caused proline, H2O2, and lipid peroxidation to be increased in all concentrations. This study showed that the silver led to the accumulation of H2O2 as a signal and induced the antioxidant defense in shoots.

Agricultural biodiversity is considered as one of the key factors determining the sustainability of agroecosystems. Preservation of biodiversity and its effective management have an important role in achieving economical, social and environmental measures of agroecosystem sustainability, hence it is essential that through precise evaluation of diversity trend in agricultural landscapes, while its preservation, effective steps also accomplish to proper management of diversity with considering the regional characteristics. Hence, current study was carried out with the aim of evaluation and analysis the changes in crop biodiversity of Isfahan province during 2003-2012 using ecological indices of diversity, including Margalef richness index, Evenness index and Shannon diversity index. Evaluation of variation trends of study indices showed that during 2003-2012 period, crop area, evenness index, Shannon index and beta diversity of Isfahan crops have significantly decreased. The downward trend of Isfahan province’s crop plants Shannon index indicated that during this period, the crop species biodiversity of Isfahan province has decreased. As, the Shannon index value of Isfahan crop species was decreased from about 2.30 in initial years of 2003-2012 period up to 2.15 in its terminal years. Results showed that significant decrease in evenness of crop area distribution and also significant reduction of crop area due to continues droughts and land use changes are among the main reasons for decline in crop diversity of Isfahan province during study period. According to cluster analysis, the townships of Isfahan province were also classified into six groups regarding their ten years average of Shannon diversity index.

Aboveground vegetation were sampled by 30 plots of 400 m2 during two periods of March and June. Seed bank flora was studied using seedling emergence method from basis of 240 soil samles (30 plot×4 replication×2 depths of 0-5 and 5-10 cm) which had been hammered by a hollow 400 cm2 metal frame. The floristic results in aboveground vegetation revealed 66 plant species belonging to 58 genera and 38 families, while a total of 103 species, 90 genera and 48 families were represented in the soil seed bank. Lamiaceae, Rosaceae, Poaceae (6 species) and Asteraceae (4 species) in the extant vegetation but in seed bank part Poaceae (11 species), Asteraceae (8 species), Lamiaceae (6 species), Scrophulariaceae, Cyperaceae and Fabaceae (5 species) were the most important families. Results also showed that Phanerophytes (33%) and Euro-Siberian (34%) were the most important biological spectrum and phytochorion respectivly in the aboveground vegetation, whereas therophytes and pluriregional regions elements (31/5%) were the most in the seed bank floras. From total of 119 plant species, the proportion of species that presented only in the aboveground vegetation, only in soil seed bank and in both of them were 16, 53 and 50, respectively. This condition confirms low similarity between above-ground vegetation and persistent soil seed bank and it also reiterate the importance of soil seed bank study for introducing more accurate capacity of plant biodiversity.

In order to investigate morphological traits of hoary cress populations, seeds of 40 populations were collected from different parts of Iran in 2013 and were sown in pots at the same condition. At the end of growth season, fifteen morphological traits were measured. Germination rate and germination percentage were also measured in laboratory. Unweighted pair-group method of arithmetic averages (UPGMA) was performed to determine the individual relationship among populations of hoary cress. Five groups were classified based on the cluster analysis of populations of hoary cress which were mainly in accordance with geographic origins. Populations belonging to the northern latitudes had lower growth due to the decline in average daily cumulative annual radiation and air temperature with increasing latitude. These variations among populations may affect their responsee to specific herbicides. Factor analysis based on PCA revealed that three factors comprise almost 88.97% of total variations that the proportion of the first, second and third components were 67.39%,12.97% and 8.60%, respectively. Fresh and dry above ground and below ground weight, total fresh and dry weight and leaf length possessed the highest positive correlation with the first factor. Leaf width, stem height, silicle width, germination rate and germination percentage possessed the positive correlation with the second factor. Dry weight of aboveground / belowground ratio and number of stem (negative) possessed the highest correlation with the third factor.

Use of superabsorbent polymers is one strategy for increasing irrigation efficiency and optimal use of rainfall in arid and semi-arid region. In order to increasing the water use efficiency in basil production as a valuable medicinal plants and sensitive to water stress, was conducted the research as a factorial experiment on the basis of randomized complete blocks design with three replications. The treatments were two superabsorbent polymers Stockosorb® (industrial) and malva leaf (Herbal) in four concentrations (0, 0.1%, 0.2% and 0.3% w/w on the basis of soil weight) with two application methods (mixed with soil only and mixed with soil roots). The results showed that all treatments and especially their interaction had significant and positive effects on some biochemical, biological, morphological traits and water use efficiency characteristic, except seeds swelling index. Both hydrophilic polymer (Stockosorb 0.2% mixed with soil and malva leaf 0.3% mixed with soil root) were able to reduce the drought stress intensity and improved water use efficiency (60%) in basil cultivation. Stockosorb® treatment %0.2 (mixed with soil), increased leaf number (149.89 per plant) and seed number (2125 number). Whereas the maximum content of chlorophyll “a” (30.74 mg. g-1) and one thousand seed weight (1.69 g/ per plant) were detected by using Stockosorb® (%0.2) when applied on soil roots. The best results were obtained for dry matter (2.34 g/ per plant) and biochemical traits (chlorophyll b (10.93 mg. g-1) and antioxidant capacity (87.03%)) with malva leaf treatment (%0.3) applied on soil roots and root respectively.

Zarcheshme protected region (no hunting area) is located at 60 km from south-west of Shahreza, north of Esferjan, 12 km from Hounejan and 130 km from Isfahan. The purpose of this study was to evaluate the floristic composition, life form spectra, chorological analysis, and determine threatened criteria, medicinal, pastoral and poisonous plants from this region. All the data from this research are first reported for this area. The results of this study showed that a total of 150 species belonging to 115 genera, 33 families in this region. Seven families, 21 genera and 25 species were belonged to monocotyledons and 26 families, 94 genera and 125 species included dicotyledons. Moreover, Asteraceae was considered one of the largest families in this region including 22 genera and 28 species. Based on Raunkiaer's method, the life forms consisting of 50% hemicryptophytes, 25% therophytes, 11% geophytes, 7% chamaephytes, 4% phanerophytes and 3% hydrophytes were detected. From the chorological point of view, 73% were allocated to Irano-Touranian elements. It is worth noting that, 29 endemic species, 78 medicinal species, 51 pastoral species and 23 poisonous species were determined in this region. Based on the threatened species criteria, there were 19 species in lower risk and one species in vulnerable case.

Studying of natural sites, ecological conditions and quantifying and qualifying characteristics of species provide important data applicable for site management. Four natural sites have been chosen to study Elaeagnus angustifolia in Western Azerbaijan Province, Iran. Hundred percent inventory were carried out to measure the quantifying and qualifying factors such as diameter at breath height (dbh), height, crown cover, number of coppices. Three soil samples were taken from each site and parameters such as pH, N, P, K, C, EC, soil texture were measured for further analysis. Regression analysis was applied in order to find any relation between diameter at breath height with total height and crown cover. For comparing different quantifying factors and production rate at various regions, Kruskall-Wallis and Mann-Whitney test as non-parametric tests were applied. A PCA is used in order to find an influence of soil type on various characteristics of productions. The average d.b.h in Malone, Osaloye-Kazem, Ghoshchi, and Rabat was 14.2,11.6, 22.5, and 18.6 cm, respectively. The average height of trees was 6.16 m in Ghoshchi, 5.13 m in Malone, 5.1 m in Oslaoye-Kazem and 4.11 m in Rabat. The average production rate was 7.9 kg in Ghoshchi and it is followed by Osaloye Kazem (6.51kg) and Rabat (5.03 kg).The results showed that there were no significant differences in production rate among the sites. Among different elements of soil, potassium was the most influencing element on the production rate while soil texture was the second most important variable. The other factors were not statistically significant.

Calotropis procera seed's has poor germination in field condition. Seed germination is a critical stage of species survival. To investigate the effects of drought (Kcl, KNo3 and PEG-6000-respectively) on seed germination a factorial experimental plans was conductec in a completely randomized block and factoriel design with three replications. In the first experiment, the main factors were 2 levels of treatment (non prim and prim) and 9 levels of drought of Kcl and KNo3 (0, -1, -3, -5, -7, -9, -11, -13, -15 bar) and 6 levels of drought PEG (0, -0.1, -0.3, -0.5, -0.7,-0.9 bar). The experiment includes two environments (Lamerd and Sistan-Baluchestan). The results indicate that the effect of the drought levels is significant on seed germination properties; however, environment has not significant effects on germination rate and its percentage. Any increase in the drought stress reduces the seed germination rate, the corresponding percentage seedlings length, the pre-treatment using. Results showed that germination percentage, germination rate, seedling dry weight and seedling length. Using common solution (Kcl -20 bar, KN03 -20 bar, PEG -1 bar) as a pre-treatment of the seeds for 3 days period will enhance the germination properties.

Taxol has been introduced as an efficient natural compound with low toxicity in the control and treatment of a wide range of cancers, including breast, uterine, ovarian and other types that its production primary source is yew trees. Indeed, the limited number of yew trees and the impossibility of direct procurement of taxol from organs natural due to the legal ban on felling of these trees have been led to use in vitro cultures as a suitable alternative for the preparation of taxol. Nowadays, plant cell, tissues and organs cultures can provide the massive and rapid propagation of many medicinal plants. The present study focused on investigating, determining and comparing the amount of produced taxol with natural tissues of Taxus baccata L. and Taxus berevifolia Nutt., in vitro. In order to induce callus, stem and leaf explants were used in WPM medium enriched with 2,4-D and Kinetin hormones. The available Taxol was measured using HPLC techniques. After the extraction process, taxol was measured and compared in normal tissues including the skin, stems and leaves. The result showed that the amount of taxol in normal tissues of both species had a similar trend so that in the leaves was more than in the stem and then in the skin, but its amounts was different in both mentioned species. It was further observed that the amount of taxol was higher in T. baccata. Moreover, the amount of taxol in calluses of T. brevifolia and T. baccata were higher than normal tissues.

The Shahid Rajaee dam has been constructed on Tajan River in the south of Sari city. High probability of algal bloom occurrence in the dams and its negative effects on economic, social activities and human health in the area indicate to the importance of algal studies (determination of abundance and structural community of phyoplankton) in this dam. Sampling was carried out in May, June, July, Agust, September, November and February at the reservoir in 2011-2012. Result showed that 107 species identified in 53 genus and 8 divisions of phytoplankton. Bacillariophyt and Pyrrophyta formed more than %90 of phytoplankton abundance. Three species namely Cyclotella meneghiniana Kuetzing,1844 ¡Ceratium hirundinella (Mueller) Dujardin, 1841 and Goniaulax polyedra Stein, 1883 showed tendensy to form mass density and showed higher bloom potential with compare to the other species in this area. Abundance of C. meneghiniana Kuetzing in warm months was significantly higher than cold months (p

P.alba and P.euphratica trees are native poplar species of Iran. P. alba for adaptability, wood production and straightness of stem form and P. euphratica for resistance of drought and salinity are important. The purpose of this study was comparison of the growth and physiological charactristics of two native poplar species and their hybrid ( P. euphratica x P. alba 44 / 9) under saline soil of Garmsar and non-saline soil of Karadj. One-year-old rooted cutting was planted with 3×3 m spacing based on randomized compelete block design with three replications in March 2010. Growth and physiological characteristics of the trees were measured according to standard procedures. Analysis of variance of growth characteristics showed that diameter, height, leaf area, specific leaf area (SLA) and leaf dry matter variables had a significant differences among poplar clones. P. euphratica and its hybrids had the highest survival percent, diameter and height values in saline soils of Garmsar. P. alba 44/9 and 58/57 clones had the lowest leaf area value in saline soils. Hybrid clone had the highest survival percent, diameter and height values in Karadj. Analysis of variance of leaf physiologic characteristics showed that chlorophyll a, chlorophyll b and carotenoids values had a significant differences among poplar clones. P. euphratica and its hybrids had more proline, soluble suger and relative water content (RWC) values than P. alba clones in saline soil. Finally P. euphratica and hybrid clones had suitable potential for wood production and resistance to salinity on saline soils of Garmsar station.

Copper is an essential micronutrient for plant, so that its shortage will affect plant metabolism. High levels of Cu can cause phytotoxicity through the generation of reactive oxygen species. This study aimed to investigate the effect of different concentrations of nanoparticles and chloride solution, 0,1,5,10 ppm on growth and morphology of basil. The findings indicated that reduction of germination percentage, germination speed and germination index in the presence of copper chloride solution was more than that of copper nanoparticles. The measurement of length, wet and dry weight of root and aerial organ showed the negative effect of increased concentrations of copper nanoparticles and copper chloride solution on these parameters. Chlorophyll a level in all plants under treatment was reduced with an increase in copper chloride concentrations. Also, increased concentration of copper chloride solution significantly increased flavonoid and total phenol in comparison with copper nanoparticles. Anthocyanin level in the plants under the influence of copper nanoparticles was reported to be higher than that of copper chloride. The results of this study revealed that copper nanoparticles exerted less toxicity effect on the basil plant growth than copper chloride solution.

Cappadocian maple (Acer cappadocicum Gled) is one of the industrial and important species of Hyrcanian forests which has a wide distribution. Due to climate changes in recent decades that rising global warming and drought its consequences and the ecological and economical value of Cappadocian maple species, it seems to be necessary to know about resistant adjustment of this species compared with different levels of drought stress. In order to investigate the effect of drought stress on growth, leaf morphological and physiological characteristics of the one-year seedlings, an experiment was designed in a completely randomized design with four levels field capacity included %100 field capacity (control), %75 (mild stress), %50 (medium stress) and %25 (severe stress) which was performed in growth chamber. The results showed that among the studied characteristics, drought stress had the greatest effect on physiological characteristics. Intensifying drought stress induces changes in amount of Chlorophyll b, peroxidase enzyme, electrolyte leakage and relative water content, whereas it had no effects on leaf morphological characteristics. Also among morphological characteristics, drought stress exertion caused to decrease the rate of leaf water. Based on results of this study and taking silt loam soil texture used, threshold of response to drought stress could be introduced %50 field capacity in this species.

Many orchid species are threatened with the danger of extinction. Here, a protocol was developed for high frequency in vitro multiplication of an endangered orchid, Orchis catasetum using plant growth regulators and iron Nano-chelate. Protocorms, as explants were cultured on Murashige and Skoog (MS) medium fortified with different concentrations of N6-benzyladenine (BA), α-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) either individually or in combination and iron Nano-chelate. A combination of 0.5 mg l-1 BA and 0.5 mg l-1 NAA was found to be suitable for maximum protocorm-like bodies (PLBs) regeneration (18.84/plantlet) from protocorm explants. The maximum number of root (6.94/plantlet) and leaf (9.50/plantlet), also the highest plant height (124.10 mm/plantlet) and root length (178.90 mm/plantlet) were obtained on MS medium supplemented with 0.5 mg l-1 BA a long with 0.5 mg l-1 NAA. Related to the effect of iron Nano-chelate, maximum plant height (82.79 mm/plantlets), maximum root number (4.76/plantlets) and root length (87.53 mm/plantlets) were observed in explants cultured in MS medium enriched with 0.13 mg l-1. Plantlets were transplanted to pots filled with perlite, wood pieces, ionolite and mineral cartridge shell (1:1:1:1), also perlite individually and transferred to the greenhouse. Upon ex vitro transfer, 100% of plants survived.

Heavy metal pollution is one of the serious problems in the world. Among the heavy metals, lead is a strong pollutant that readily accumulates in soils and sediments. This study was designed to find out the effect of Pb toxicity on developmental and physiological particularity in Petunia hybrida L. For this purpose, Petunia seeds were planted in green housed condition and different concentrations of lead acetate including 400, 800 and 1200 µmol/L were spread on the plants, and control group were spread with water. Results showed that the percentage of germination, root and shoot length, leaf area, plant height, the amount of chlorophyll a, b and a were reduced, and an increase in the activity of catalase and peroxidase under lead treatment were observed. The peroxidase enzyme activity increased up to 800 µmol /L of lead and then slightly decreased at 1200 µmol /L. Lead treatment didn’t have a significant effect on total protein content. The results of this study showed that the toxicity of Pb had detrimental effects on plants and although plants dont need to heavy metal, uptake by plants and leading to negative effects on their function.

Fatty acids accumulation pattern and oil oxidizability during fruit ripening of two olive cultivars of high and low oleic acid, Shengeh and Mary,were studied respectively while the environmental conditions kept constant. Samplings were done at 90, 120, 150 and 180 days after flowering (DAF) and the fatty acid composition was determined by gas chromatography (GC) after seed oil extraction by n-hexane. Analysis of variance (ANOVA) showed that accumulation of stearic, oleic and linoleic acids were significantly influenced by genotype. Indeed, there was a significant correlation between time andboth oleic and linoleic acids. Overall measurements demonstrated higher palmitic and linoleic acids in Shengeh cv. and higher steraric and oleic acids in Mari cv. During four studied stages olive development . Also, there was a positive correlation between linoleate and calculated oxidizability value (COX). Increasing pattern of oleic acid content in both genotypes implies the inhibitory effect of oleic acid on the phospholipase activity of oleosins leading prevention in out-course germination It is worthy to note that genotype plays a crucial role in fatty acid content in development stages as seed oli acid content in mary cv. is higher then Shengeh.