Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research
Year:2016 | Volume:24 | Issue:2|Papers Count:20

Thymus vulgaris is one of the most important medicinal plants with more than 20 types of known important chemical compositions. A gene named 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) acts as an important control point, as this is the first committed step in the MEP pathway. g- terpinene is a key component in essential oil of thyme which constituted up to 30% of the essential oil in the species and is biosynthesized viag- terpinene as a penultimate precursor. Different cytochrome P450 including CYP71D178 and CYP71D182 are involved in the biosynthesis of thymol and carvacrol in thyme and oregano via the g- terpinene as an intermediate. The aim of the present work was to study the expression patterns of genes involved in thymol and carvacrol biosynthesis including DXR, g- terpinene synthase, CYP71D178 and CYP71D180 genes in flowers and leaves of thyme. Gene expression analysis of DXR, g- terpinene synthase, CYP71D178 and CYP71D180 genes were carried out by semi-quantitative RT-PCR technique. The relative gene expression of flowers compared with leaves for DXR, g- terpinene synthase, CYP71D178 and CYP71D180 genes were 1.7, 2.7, 1.9 and 2 fold higher, respectively and the gene expression intensity varied for each gene. Expression of aforementioned genes in glandular trichomes were high, hence the higher gene expression in flowers might be related to higher density of glandular trichomes. Based on these results, higher content of essential oils in flowers compared to leaves is most likely further related to the higher expression of related genes in flowers rather than leaves.

Betula pendula Roth produces a range of biologically active terpenoids such as betulin and betulinic acid. The compounds with cytotoxic effects which have been used for their medicinal properties. Agrobacterium-infected hairy roots are characterized by high growth rate and genetic stability that can be provided noticeable amounts of the biological material. In this study, production of hairy roots by B. pendula was investigated on different explants, media and A. rhizogenes strains. Growth rate of hairy roots were studied during 20 days and the terpenoids content (betulin & betulinic acid) were assayed by HPLC. Hairy root cultures were established 20 days after infection by infecting bark segments of B. pendula by Agrobactrium strains of C58C1and LB9402 in WPM medium. Growth of hairy root by lines of C58C1 strain (D and E lines) and one line fromLB9402 strain (LB1) were significantly better than others. The most betulin content was observed in the hairy roots, 8 days after culture, which was about 0.47 mg g-1 dry waight (DW). Furthermore, the most amount of antioxidant activity (75%) was assessed on E line roots, 20 days after cultures. Although the highest content of betulinic acid (0.6 mg g-1 DW) was obtained by LB1 lines but betulin content and antioxidant activity were considerably less than other hairy root lines. Results indicated that due to higher relative performance, E line of hairy roots could be used for analysis of terpenoids and pharmaceutically important metabolites in future studies.

To examine morphological variability of leaves and fruits of wild pear (Pyrus glabra) among different populations, leaf and fruit samples of 48 trees from four populations at altitude of 2150 m above sea level (Tange Sorkh), 2250 m (Vezg), 2450 m (Gorgo) and 2550 m (Mahparviz) located in Boyer Ahmad city, Iran, were collected. Then, 16 quantitative and qualitative leaf and fruit morphologic traits were recorded. Analysis of variance showed that among the studied parameters, lamina length, petiole length, lamina width at 0.1 and 0.9 of leaf lengths, maximum width of lamina, relative length of petiole, leaf shape, small and large diameter of fruit showed significant differences among the populations. Results of principal components analysis showed traits such as maximum width of lamina, lamina length, leaf dry weight, leaf tip angle, and leaf specific surface, played the most important role in grouping the genotypes and populations. In addition, leaf tip angle, leaf dry weight, and leaf surface had the highest coefficient of variation. Results of discriminate analysis showed that effective traits in isolation of the populations including leaf shape and fruit large diameter. Finally, leaf base shape, and large diameter of fruit remained unchanged resisting environmental changes (less variability) can be used as good traits to identify and separate genotypes of wild pear.

Twenty five SCoT primers were employed to investigate genetic diversity of 42 samples of Ziziphora tenuior from different geographical regions of Iran. A total of 209 fragments were amplified and 66% of them were polymorphic. Most amplified polymorphic fragments (10) were related to a primer named SCoT-54, while another primer named SCoT-20 showed the lowest (2) amplified polymorphic bands. Average number of amplified bands for primers was 8.36, while average number of polymorphic bands was 5.53. Polymorphic information content and discrimination power (PICD) varied between 0.217 in SCoT-31 and 0.074 in SCoT-30 with an average of 0.156. Similarity matrix was generated using Jaccard coefficient, Cluster analysis was carried out by UPGMA algorithm and principle coordinate analysis. According to the cluster analysis within the similarity coefficient of 0.7, Ziziphora samples were divided into 7 groups. Based upon similarity matrix, the lowest similarity (0.59) was found for two samples from Naein and Yasuj. The highest similarity (0.98) found between two samples from Damghan and Garmsar within the same geographical region. Analysis of molecular variance (AMOVA) suggested significant genetic differences within the samples. In fact, 89% of variation occurred within the species, whereas 11% of the variation was observed among the samples of Ziziphora tenuior. The results finally indicated moderate genetic diversity among the studied genotypes.

Zinc as an essential element for plant growth, plays an important role in many metabolic processes of plants, such as limonene synthase gene expression pathway. Limonene synthase is considered as an important enzyme in volatile oil biosynthesis that plays significant role in plant defensive reactions. In the present study, limonene synthase gene expression in Cumin was evaluated in presence of different concentration of Zinc elicitors based on a completely randomized design. Total RNA was extracted and cDNA synthesis was performed and Real Time PCR quantity assay method was used for limonene synthase gene expression. Results of the comparison of gene expression with Duncan's multiple range tests in different concentrations showed that in treated plants, there was a direct correlation between increasing of Zinc concentration up to 100 mM and limonene synthase gene expression. Limonene synthase gene expression by increasing production of monoterpens may produce more volatile oils in plant species and thus protects the plant against herbivores.

Moringa peregrine (Forssk.) Fiori is a valuable species with a vast utilization in nutritional, medicinal, health, and industrial aspects which is under genetic erosion and extinction threat both in Iran and all around its global habitats. Due to its importance and roles, study on its biological aspects such as genetic variation may accelerate its development. For this reason, 11 single trees of four different plant populations of the species, collected from South part of Baluchestan province, of Iran, were used in this study. Extracting, seed storage proteins of the genotypes, SDS-PAGE method of electrophoresis was used to evaluate genetic variation between and within the populations on macromolecule protein level. Performing electrophoresis, fixation and staining the protein bands, presence, or absence of the protein bands were investigated. Regarding the protein bands, based on qualitative criterion, there were not remarkable differences between the studied genotypes and regions to be used for discriminating between the studied genotypes and populations. In contrast with the qualitative differences there were plenty of quantitative differences between the studied genotypes and populations. Since gene flow and genetic interchange between the natural populations through seed transfer is rarely happening in the nature, it is expected to have plant populations with less interchange and more genetic differentiation.

Sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) is a medicinal, drought tolerant, nitrogen fixing and forest pioneer plant species. In this research, for the first time in Iran, molecular identification of the species distributed in different habitats of the country was carried out comparing to the known subspecies distributed worldwide. Specimens were collected from five habitats located in Alborz, Mazandaran, East and West Azerbaijan, and Qazvin provinces. Nuclear ribosomal ITS marker was used in the molecular study. After DNA extraction and PCR application, sequences obtained in this study were aligned with those obtained from Gene-Bank belonging to all sea buckthorn subspecies. The aligned sequences were analyzed using Bayesian and TCS phylogenetic methods. Results showed that the specimens collected from Alborz, Mazandaran, East Azerbaijan and Qazvin belong to the Caucasian subspecies, E. rhamnoides subsp. caucasica, but the specimen sampled from West Azerbaijan with two mutations is a new subspecies. Therefore, it is introduced as E. rhamnoides subsp. azerbaijanica

Plantago psyllium L. is from "Plantaginaceae" family and one of the most important medicinal plants with wide distribution in Iranian flora. In order to evaluate responses of Plantago psyllium L. to salinity, an experiment was conducted using tissue culture technique as well as somaclonal variation for identification and production of tolerant genotypes. The experiment was performed based on a completely randomized design with 12 treatments and 15 replications on each treatment. Seed germination percentage was 84%. Hypocotyl and root explants showed the highest and the lowest callus induction in non-saline (control) conditions respectively. In the terms of stress condition percentage of callus induction was decreased by increasing NaCl concentration on all of the three explants. Hypocotyl and root callus showed the highest and the lowest percentage of regeneration. Hypocotyl and root explants showed the highest and the lowest dry and fresh weight at all concentrations of NaCl. Also increment of NaCl concentrations led to increment of sodium and decrement of potassium ingredients of the callus. Amount of calcium varied by increasing NaCl concentration. Regenerated plants transferred to MS medium for root initiation. Then the seedlings were transferred to soil to set seed. Generally, in vitro selection is a suitable method for identification and selection of the tolerant genotypes to salinity in Plantago psyllium.

Black cumin (Nigella sativa) is one of the most important medicinal plants belongs to Ranunculaceae. In spite of its significance in pharmaceutical industry, tissue culture and micropropagation of the species is not well studied yet. Hence, based on the issue we aimed to study its callogenesis and regeneration on leave explants of the species. In vitro provided explants of leave were cultured on MS medium supplemented with NAA (0.5, 1, 1.5 mgL-1) and BAP (0.2, 0.5, 1 mgL-1). Half MS medium supplemented with 0.5, 1 and 1.5 mgL-1 NAA and IBA were used for rooting the regenerated shoots. Results showed that higher percentage of callogenesis was observed on MS medium supplemented with 0.5 mgL-1 NAA and 0.5 mgL-1 BAP. Shooting was observed on MS medium (1mgL-1 BAP) and rooting on half MS (1 mgL-1 NAA), respectively. Results indicated that callogenesis, shooting and rooting of black cumin are highly affected by hormonal combination levels.

In order to introduce new poplar hybrid clones (“Mofid” and P. ´ albaeuphratica) for commercial wood production in different parts of Iran, ecological range of productivity of the hybrids have to be determined. Therefore, adaptability of the hybrid clones, "Mofid" and its reciprocal cross hybrid (P. ´ albaeuphratica), along with Populus alba L. and P. nigra, as local clones, were investigated. The experiment was conducted based on a randomized complete block design with three replications. Three hundred individual cuttings of the clones were planted in 100 square m experimental plots by spacing of 2 ´ 2 m. Analyses of variance was performed on quantitative and qualitative characters recorded during four years. Results indicated that there were highly significant differences between the clones at 0.01 level of probability. P. ´ albaeuphratica hybrid showed higher diameter at breast height (4.98 cm), trunk height (2.08 m) and total height (5.24 m) than others two clones. Low level of breast height diameter and total height were observed for P. nigra L. clone as a local poplar clone. Mofid was sensitive to winter and spring cold conditions (below -30oC), While P. ´ albaeuphratica showed a high level of cold tolerance to the mentioned temperature.

Effects of drought stress on seed yield and yield components in fennel genotypes was evaluated at research field of college of Aburaihan, University of Tehran, Iran during 2013. Experiment was carried out in split plot arrangement based on a randomized complete block design (RCBD) with three replications. Normal irrigation and drought stress treatments were assigned to main plots and fennel genotypes including two drought tolerant synthetic cultivars (early and medium maturity synthetic cultivars) and their four elite parents (Fasa, Meshkinshahr, Fozveh and Hashtgerd) were randomized in subplots. Analysis of variance showed that effects of drought stress on number of umbels, number of umbellate, seed yield and biological yield were significant. Drought stress reduced all measured traits and seed yield (40%) was affected the most. Result showed significant differences among the genotypes for all of the studied traits. Mean comparison of the genotypes showed that the highest seed yield belonged to Fozveh (1125 kg/ha) in normal condition and lowest seed yield belonged to Fasa (434 kg/ha) under drought stress. Early and medium maturity synthetic cultivars had the highest seed yield in drought stress conditions. Stress tolerance score (STS) for genotypes were calculated. Early and medium maturity synthetic cultivars with the highest amounts of STS were introduced as the best genotypes with drought tolerant. Finally based on the results, the cultivars in environments with variable climate, especially water shortage, can produce satisfactory yield.

Origanum vulgarssp. gracile is one of medicinal plants belonging to Lamiaceae family. Carvacrol was detected as a dominant component of essential oils of the species. Effects of different concentrations of 2, 4-Dichlorophenoxy Acetic Acid (2, 4-D) in combination with benzyl adenine (BAP) were investigated on callus induction of various explants (Cotyledon, Hypocotyl, Node, Shoot Tip and leaf) of the species. Interaction between culture media and explant types was significant at 1% Level of probability. The highest percentage of callus induction (100%) was obtained on MS medium supplemented with 1 and 3 mg l−1 2, 4-D on node explants. Maximum callus induction (93.3%) was observed on MS medium supplemented with 3 mg l−1 2, 4-D. No callus induction (0%) was observed on control and MS medium supplemented with 0.1 mg l−1 BA on leaf explants. Higher percentage of embryogenic callus production was obtained on MS medium supplemented with 1 mg l−1 2, 4-D in combination with 0.1 mg l−1 BAP on shoot tip explants. Percentage of embryogenic induction was the lowest on hormone free MS medium and media containing 0.1 mg l−1 BAP in all explants and MS media supplemented with 5 mg l−1 2, 4-D on hypocotyl explant. By increasing 2, 4-D concentration, embryogenesis was decreased and maximum embryogenesis percentage was obtained by shoot tip and node explants. Effects of BAP on shoot regeneration from explants, the highest shoot regeneration (100%) on nodes and shoot tip explants on hormone free media and MS media fortified with 1 mg l−1 BAP were obtained.

To determine essential oil yield stability in different populations of thyme (Thymus kotschyanus), 20 plant populations were examined in normal conditions at 11 stations, consisted Damavand, Esfahan, Golestan, Hamedan, Khorasan, Markazi, Qom, Tabriz, Tehran, Yazd and Zanjan. Data were analyzed in split plot in location design. Based on combined analysis of variance, genotype ´ location interaction was significant at (p>1%). This showed differences of the studied populations in yield and response to different conditions in eleven locations. In Graphical analysis, 11 environments were divided into 3 Mega environments. In mega environments Khorasan, Qom, Markazi, Damavand, Yazd, Zanjan and Tehran, genotypes 5, 27, 51 and 54 showed special compatibility. Genotypes 3 and 17 in Tabriz and Hamadan mega environment and genotypes 10, 8, 70 and 50 in mega environment of Golestan showed special compatibility. Assessment based on essential oil yield and stability of genotypes showed that accessions 5, 54 and 29 were suitable accessions. Graphical analysis of relationships between the environments, Khorasan, Qom, Markazi and Damavand, formed a group environment. Khorasan, Tabriz, Isfahan and Golestan locations showed significant role in differentiation of the studied genotypes. Based on graphical analysis of relationship between the genotypes, genotypes of 54 (Naghade), 27 (unknown 1), 51 (Tehran), 56 (Zarand) and 5 (Qazvin 2) formed a high production group presenting special compatibility to mega environment of Khorasan, Qom, Markazi, Damavand, Yazd, Zanjan and Tehran. The mentioned genotypes could be used for thyme cultivation in the mentioned areas.

In order to evaluate heritability of agro-morphological characters as well as study of relationship between genetic diversity with geographical factors in Einkorn wild wheat populations (41 accessions consisted of 33 accessions of T. boeoticum and 8 accessions of T. urartu species), an experiment was conducted based on a randomized complete block design with three replications in research station of University of Tabriz, Iran during 2011-2012 growing seasons. Analysis of variance showed significant differences among the accessions for all of studied characters except numbers of total tiller and fertile tiller. Mean comparison also revealed significant differences between the two species in terms of all characters except leaf width as well as weight of total spikes and harvest index. For both of the species, heritability and variation coefficients indicated high level of genetic variation for agro-morphological characters. According to correlation coefficients, a positive and significant relation was found among the studied characters. However, only correlation between latitude and spike length as well as altitude and number of total tillers were positive and significant. Clustering of the accessions on the basis of all characters and geographical factors produced two main groups, so that in both dendrograms grouping of accessions were greatly consistent with each other. Accessions with closer altitude and latitude were allocated to similar groups. On the whole, remarkable level of genetic diversity among Einkorn wheat, especially accessions collected from Kermanshah and Lorestan provinces was revealed, implying special attention to germplasm of the areas is required.