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Taxes play a crucial role in the economic development of a country. The purpose of this paper is to analyse and compare the tax systems of Arab countries, as well as the role they play in the lives of our peoples. The goal of this guide is to ensure a better understanding on the Real Estate Transaction Tax (RETT) in Saudi Arabia, Egypt, and Jordan, as well as to explain the philosophy behind it in these Arab countries. Each tax system of the analysed countries is scrutinized and compared in order to create an ensemble image of the tax systems. The main results of this comparative study show that the Kingdom of Saudi Arabia is closest to the goal of realizing social justice, for which the tax systems were originally found, through the percentage obtained in all cases of the system, followed by Jordan. Secondly, Egypt is one of the countries with mostchanges in the taxsystem. Since the three countries from the Arab region and their peoples share many characteristics, this study recommends the experiment of tax coordination between Arab countries as a tool to achieve economic integration.

Low-pressure powder injection moulding (LPIM) is a cost-effective manufacturing technology used to fabricate complex-shaped parts with high mechanical properties at low- or high-volume production. ...

Sahendian savory (Satureja sahendica Bornm) is a medicinal plant species which produces valuable secondary metabolites including thymol, p-cymene and γ-terpinene. In this study, optimization of hairy roots culture in S. sahendica using Agrobacterium rhizogenes was efficiently established. High frequency of genetic transformation was obtained using node and internode explants and three bacterial strains (ATCC 15834, A4, and LBA 9402). However, leaf explants showed no susceptibility to induce hairy roots with the A. rhizogenes strains. The node explants and LBA 9402 strain were the best combination for root induction. Infection time of 20 min caused greater transformation occurrence compared to 10 and 30 min, respectively. Node explants infected with LBA 9402 were found to produce more transformants upon co-cultivation for 2 days. The maximum induction of hairy roots was obtained from bacterial infection at a density of OD600 = 0.8. Polymerase chain reaction by gene-specific primers from rol B gene confirmed the positive transformation events. S. sahendica efficiently provided and produced a large number of hairy roots which could be used for the production of secondary metabolites or other molecular and biotechnological applications. Production of thymol an important secondary metabolite of S. sahendica from hairy root cultures was confirmed by TLC and GC analysis. Elicitor-treated hairy root cultures with methyl jasmonate and ammonium nitrate produced more amount of thymol compared to untreated roots. These results demonstrate that secondary metabolite production such as thymol in hairy root culture of Sahendian savory could be used to increase low secondary metabolite production in this valuable medicinal plant.

Pyrethrum (Chrysanthemum cinerariaefolium) is a plant from the Asteraceae family discovered as a plant-based insecticidal source which is producing beneficial secondary metabolites such as sesquiterpenes and pyrethrins, hence raised attention due to the insecticidal properties of its secondary metabolites. To improve our knowledge about the biosynthesis of sesquiterpenes and pyrethrin I, we directed a survey to analyze the gene expression in different developmental stages of leaves and also in chloroform dipped leaves (to remove glandular trichomes). Along with this, histochemical experiments were carried out on leaves to detect the accumulation site of lipids, monoterpene phenols, and sesquiterpenes. Gene expression results showed that chrysanthemyl diphosphate synthase (CDS), farnesyl diphosphate synthase (FDS), and 13-Lipoxygenase (13-LOX) putative genes were highly expressed in intact leaves (leaves with glandular trichomes). In contrast, their expression significantly decreased in chloroform dipped leaves (without glandular trichomes). Also, the higher expression of genes that are related to the biosynthetic pathways of sesquiterpenes and pyrethrin I was observed in young leaves compared with the leaflets and fully-expanded leaves. The obtained results demonstrate that glandular trichomes’ relative density changes markedly during the developmental stages of leaves and, consequently, influences the transcript levels of trichome-specific genes.

Due to the accumulation of various useful traits over evolutionary time, emmer wheat (Triticum turgidum subsp. dicoccum and dicoccoides, 2n = 4x = 28; AABB), durum wheat (T. turgidum subsp. durum, 2n = 4x = 28; AABB), T. timopheevii (2n = 4x = 28; AAGG) and D genome containing Aegilops species offer excellent sources of novel variation for the improvement of bread wheat (T. aestivum L., AABBDD). Here, we made 192 different cross combinations between diverse genotypes of wheat and Aegilops species including emmer wheat × Ae. tauschii (2n = DD or DDDD), durum wheat × Ae. tauschii, T. timopheevii × Ae. tauschii, Ae. crassa × durum wheat, Ae. cylindrica × durum wheat and Ae. ventricosa × durum wheat in the field over three successive years. We successfully recovered 56 different synthetic hexaploid and octaploid F2 lines with AABBDD, AABBDDDD, AAGGDD, D1D1XcrXcrAABB, DcDcCcCcAABB and DvDvNvNvAABB genomes via in vitro rescue of F1 embryos and spontaneous production of F2 seeds on the Fl plants. Cytogenetic analysis of F2 lines showed that the produced synthetic wheat lines were generally promising stable amphiploids. Contribution of D genome bearing Aegilops and the less-investigated emmer wheat genotypes as parents in the crosses resulted in synthetic amphiploids which are a valuable resource for bread wheat breeding.

Chickpea (Cicer arietinum L.) is one of the most important legumes infected with many pathogens including fungal pathogens. One of the most important devastating fungal pathogens in chickpea is Ascochyta rabiei (Pass.) Labr. which causes up to 100% reduction in yield. In the present work, the expression patterns of AFP-ca, CaD2, LRR and PGIP genes were studied in response to Ascochyta rabiei in two susceptible and resistant chickpea genotypes. The experimental system was conducted in greenhouse, for both inoculated and mock-inoculated plants (control). RNA was isolated from Icc 12004 (resistant) and FLIP 82-150c (susceptible) genotypes in 0, 6, 12, 24, 48, 72 and 96 h after inoculation. The expression of the genes was measured in susceptible and resistant plants via semiquantitative RT-PCR. Results showed higher expression of all three genes in resistant genotype compared with susceptible one. Results showed that the candidate genes from antimicrobial families (CaD2 and AFP-ca) were up-regulated in resistant genotypes at early hours after inoculation (6–24 hpi), and also for PGIP from galacturonase-inhibiting protein families, the maximum expression was observed at early hours of inoculation to 48 hpi. In general, we concluded that all genes studied in this investigation contribute to plant–pathogen interaction and all of them can increase the resistance responses to Ascochyta blight disease.

Nigella sativa (Black cumin) has many applications in food and pharmaceutical industries. Thymoquinone has been considered as a main effective compound in N. sativa seeds and attracted researchers' attention mainly due to its medicinal potential. In this study, the essential oil components of leaves, flowers and seed developmental stages including half black seeds, soft black seeds and hard black seeds were analyzed in N. sativa. Whereas no terpenes were detected in flowers and leaves, seeds showed an essential oil composition that increased in its thymoquinone content during seed maturation. To study the proposed first step of thymoquinone biosynthesis, the formation of γ-terpinene from geranyl diphosphate (GDP), we identified and functionally characterized a γ-terpinene synthase (NsTPS1) in N. sativa. This monoterpene synthase was identified in RNA sequence data derived from seeds. After heterologous expression in Escherichia coli, partially purified NsTPS1 converted GDP to γ-terpinene. NsTPS1 is the first functionally characterized terpene synthase from N. sativa and displays a higher similarity to other terpene synthases from Ranunculaceae than known γ-terpinene synthases from more distant plant species. Characterization of NsTPS1 elucidates the first dedicated step in the biosynthesis of thymoquinone in N. sativa and paves the way towards metabolic engineering for high-level thymoquinone production.

Yarrow (Achillea millefolium) is a medicinal plant from the Asteracea which biosynthesize different secondary metabolites especially terpenes and phenylpropanoids. To improve our understanding of the regulatory mechanisms behind the biosynthesis of these compounds we analyzed the expression of some genes associated with the biosynthesis of terpenes and phenylpropanoids in different tissues and in response to trans-cinnamic acid (tCA) as an inhibitor of PAL activity. Isolation and expression analysis of DXR, GPPS, PAL and CHS genes together with linalool synthase (LIS) as monoterpene synthase was conducted in different developmental stages of leaves, flowers and in response to trans-cinnamic acid (tCA). Differential expression of these genes observed in different tissues. tCA up-regulated the biosynthetic genes of monterpenes and down-regulated the biosynthetic genes of phenylpropanoids. Gene expression analysis in intact leaves and leaves without glandular trichomes showed that DXR, LIS, PAL and CHS are highly expressed in glandular trichomes while GPPS expressed ubiquitously. Analysis of essential oils composition showed that sesquiterpenes and monoterpenes are main compounds; in which from 57 identified compounds the highest were germacreneD (% 11.5), guaiol (%10.38), spatulenol (%8.73) and caryophyllene oxide (%7.48).

Digitalis nervosa is an important medicinal plant species belonging to the family of Scrophulariaceae that has the potential to be used for heart failure. 3β-hydroxysteroid dehydrogenase (3β-HSD) is a key gene in the biosynthesis of cardenolides for making digitalis effective compounds, hence identification of this gene is important for genetic engineering purposes towards increasing the yield of cardiac glycosides. In addition, mRNA-like non-coding RNAs (mlncRNAs), a class of long non coding RNAs, play key roles in various biological processes and may affect cardenolides pathway in digitalis plants. In the present work, full sequence of 3β-HSD was isolated from Digitalis nervosa. Gene expression patterns of 3β-HSD along with three mlncRNAs including mlncRNA23, mlncRNA28 and mlncRNA30 were studied and the results indicated that they are differentially expressed in different tissues including roots, stems and leaves, with the highest expression levels in leaves. Moreover, the transcript levels of these genes affected by the cold and drought stresses. The results obtained from the present study is important in order to understand the potential role of mlncRNAs in digitalis plants, especially in response to abiotic stresses.

Low-pressure powder injection molding (LPIM) is a cost-effective technology for producing intricate small metal parts at high, medium, and low production volumes in applications which, to date, have involved ceramics or spherical metal powders. Since the use of irregular metal powders represents a promising way to reduce overall production costs, this study aims to investigate the potential of manufacturing powder injection molded parts from irregular commercial iron powders using the LPIM approach. To this end, a low viscosity feedstock was injected into a rectangular mold cavity, thermally wick-debound using three different pre-sintering temperatures, and finally sintered using an identical sintering cycle. During debinding, an increase in pre-sintering temperature from 600 to 850 °C decreased the number of fine particles. This decreased the sintered density from 6.2 to 5.1 g/cm3, increased the average pore size from 9 to 14 μm, and decreased pore circularity from 67 to 59%.

One of the most important issues in crop production is the use of agrochemicals. The use of synthetic or manufactured chemicals on crops has made a frightening image of health problems. A concern about chemical residues on food products has led to seek for new alternative compounds with fewer side effects on humans and environment. Pyrethrum (Chrysanthemum cinerariaefolium) belongs to the Asteraceae family is one of the most important resources of natural insecticides which produce pyrethrin I. Pyrethrin I has an acidic moiety and an alcohol moiety, the acidic moiety of these molecules is a monoterpene with a cyclopropane ring and biosynthesized via 2-C-methylerythrol 4-phosphate pathway (MEP) and alcohol moiety is biosynthesized via the lipoxygenase pathway through membrane lipids. At the end, the acidic moiety and alcohol moiety from separate pathways conjugate together by TcGLIP enzyme, a kind of GLIP lipase family. Based on the importance of pyrethrin I as a natural insecticide in pyrethrum partial sequences of 1-deoxy d-xylulose 5-phosphate synthase (DXS) gene from the MEP pathway and Allene oxide synthase (AOS) gene from the lipoxygenase pathway were isolated by specific primers to study their expression patterns in different conditions. Along with this, gene expression patterns of DXS, chrysanthemyl diphosphate synthase, farnesyl diphosphate synthase, GLIP lipase (TcGLIP), AOS and 13-lipoxygenase were investigated under abiotic elicitors including trans-cinnamic acid, methyl jasmonate, salicylic acid and ultra-violet ray by RT-PCR to determine the effect of aforementioned elicitors on transcript levels. Results showed that the expression of genes in the biosynthetic pathway of pyrethrin I under methyl-jasmonate, salicylic acid and ultra-violet ray treatments were up-regulated in compared with control plants.

Given the importance of borage (Borago officinalis L.) as a medicinal herb, androgenic studies are necessary in order to speed up the breeding programs of this plant species. In this work, we evaluated the effect of silver nitrate, activated charcoal, ascorbic acid, and polyvinylpyrrolidone (PVP), previously described as antibrowning agents and promoters of androgenesis. Adding silver nitrate at a concentration of 5 mg L-1 significantly enhanced the androgenic responses of cultured anthers up to ~2-fold for total calli production (53.33%) and up to ~2.5-fold for embryonic calli and embryo formation (30% and 0.3 embryos/anther, respectively) compared to control culture medium. Culture media containing 5 and 10 mg L-1 silver nitrate and 2 mg L-1 PVP significantly reduced the callus browning and led to increased callus viability in borage cultured anthers. We also evaluated the effect of various combinations of picloram with 2-isopentyl adenine and 2,4-dichlorophenoxyacetic acid (2,4-D) as growth regulators in the standard protocol. Significantly better results were obtained by adding 2 mg L-1 picloram in combination with 2 mg L-1 2,4-D in culture medium. This medium produced the highest frequencies of callogenesis (48.33%), embryogenic calli (20%), and embryo formation (0.2 embryos/anther) compared to control and other growth regulator combinations.

Black cumin (Nigella sativa) is a medicinal herb belongs to the Ranunculacea which raised attention due to its pharmaceutical properties. Medical significance of N. sativa mainly attributed to its oxygenated monoterpenes and triterpene saponins which are biosynthesized via the methyl erythritol phosphate (MEP) and MVA (mevalonic acid) pathways, respectively. In order to improve our understanding of monoterpene and triterpene metabolism the partial sequence of a hypothetical monoterpene synthase (MTS) was isolated from N. sativa for the first time and subsequently the relative gene expression of two genes of monoterpene metabolism including geranyl diphosphate synthase (GDS), the isolated monoterpene synthase (MTS) and two genes of triterpene saponins biosynthesis including squalene epoxidase (SQE) and β- amyrin synthase (βAS) were monitored in response to two universal abiotic elicitors including methyl jasmonate (MJ) and salicylic acid (SA), also in different tissues of N. sativa including leaves, stems, roots, capsules and immature seeds. Results of semi quantitative reverse transcription PCR revealed differential regulation of these genes in N. sativa tissues and also in response to abiotic elicitors. Each gene followed a different expression profile and expression level in target tissues. The expression of all studied genes were up-regulated by exogenous application of MJ and SA on N. sativa leaves (at 24 h after treatments), except of GDS which its transcript was not induced by SA. The higher expression of these genes in response to abiotic elicitors might reflect an elevation in the corresponding metabolites; hence elicitation is an applicable tool for enhancement of pharmaceutically active mono/triterpenes in N. sativa.

Culture shock is an important issue and is the result of movement of individuals from one place to another. The differences between the old environment and the new environment are the major causes of culture shock. The individuals may feel insecurity, disorientation, anxiety and so forth as a result of culture shock. The goal of this research study is to analyze the causes of culture shock and how international students at Eastern Mediterranean University (EMU) perceive them. In this study, factors were identified and questionnaires were distributed to three-hundred fifty international students in order to measure how culture shock elements vary based on gender, country of origin, educational level, age, length of stay and monthly income. Major causes of culture shock were infrastructure, service quality, weather, and language. Also, the results of this research showed there are significant differences between international students‟ demographic characteristics and culture shock causes. The results of this thesis imply that almost all international students should expect to experience culture shock because they may find the new environment challenging to adjust to. As a result, we suggested that international students should collect enough information about the host culture, education system etc. and try to build relationships with locals in order to understand their society. Keywords: International students, culture shock, culture shock elements, Eastern Mediterranean University, North Cyprus. ÖZ: Kültür şoku, bireylerin yaşadıkları bir yerden başka bir yere taşınması sonucu, yeni çevredeki farklılıklara adapte olmakta yaşanan zorluklar nedeniyle ortaya çıkan önemli bir konudur. Kültür şokunun yaşanması, bireylerde güvensizlik, yönelim bozukluğu, endişe v.b. neden olabilmektedir. Bu araştırma, Doğu Akdeniz niversitesi'nde öğrenim gören uluslararası öğrencilerin kültür şoku yaşamalarının nedenlerini ve öğrencilerin bu şoku nasıl algıladıklarının araştırılmasını amaçlamaktadır. Kültür şokuna neden olan unsurların, öğrencilerin cinsiyetleri, menşe ülkeleri, eğitim düzeyleri, yaşları, kalış süreleri ve aylık gelirlerine göre nasıl değişim gösterdiğini ölçmek için üçyüz elli öğrenciye anket dağıtılmıştır. Elde edilen bulgular, uluslararası öğrencilerin farklı demografik özellikleri ile kültür şoku nedenleri arasında belirgin farklılıklar olduğunu göstermiştir. Tezde elde edilen sonuçlara bakıldığında, hemen hemen tüm uluslararası öğrencilerin, uyum sağlamaları zor olan yeni çevre koşulları nedeniyle farklı kültür şoku faktörlerinden etkilenebileceklerini göstermiştir. Sonuç olarak, uluslararası öğrencilere, kültür şokundan etkilenmemeleri için yeni kültür, eğitim sistemi vb. hakkında yeterli bilgi toplamaları yanında yerel halkla ilişkiler kurmaları önerilebilecektir. Anahtar Kelimeler: Uluslararası öğrenciler, kültür şoku, kültür şoku unsurları, Doğu Akdeniz niversitesi, Kuzey Kıbrıs. Master of Business Administration in Business Administration. Thesis (M.B.A.)--Eastern Mediterranean University, Faculty of Business and Economics, Dept. of Business Administration, 2018. Supervisor: Assist. Prof. Dr. Doğan Ünlücan.

Accumulation of defense metabolites is an adaptive response to heavy metals in plants. However, deployment of multiple classes of defense metabolites under cadmium (Cd) and copper (Cu) toxicity is not understood. Here, the responses of parthenolide and phenylpropanoids were examined. Quantification of parthenolide and phenylpropanoids, and the expression of parthenolide biosynthesis genes were performed in feverfew leaves. Photosynthetic and physiological analysis of feverfew seedling treated with Cd and Cu were used to confirm the relationship between concentration of heavy metals and secondary metabolites accumulation. In addition, we examined the role of trans-Cinnamic acid (CA) as a phenylalanine ammonia-lyase (PAL) inhibitor alone or together with different Cd and Cu concentrations on plant growth and metabolites accumulation. Application of different Cu concentrations alone was more phytotoxic than respective Cd concentrations alone in terms of plant growth, photosynthesis, and oxidative status; however, addition of CA improved these attributes compared with their respective treatments alone. The results also revealed the repressing parthenolide biosynthesis versus phenylpropanoids when plants treated with heavy metals, whereas CA treatment showed the inverse effect. This study provides valuable information into the response of feverfew plants to Cd or Cu alone or together with a PAL inhibitor by linking stress-related physiological responses to changes in metabolites.

Digitalis nervosa is an important medicinal plant species belonging to the family of Scrophulariaceae that has the potential to be used for heart failure. 3β-hydroxysteroid dehydrogenase (3β-HSD) is a key gene in the biosynthesis of cardenolides for making digitalis effective compounds, hence identification of this gene is important for genetic engineering purposes towards increasing the yield of cardiac glycosides. In addition, mRNA-like non-coding RNAs (mlncRNAs), a class of long non coding RNAs, play key roles in various biological processes and may affect cardenolides pathway in digitalis plants. In the present work, full sequence of 3β-HSD was isolated from Digitalis nervosa. Gene expression patterns of 3β-HSD along with three mlncRNAs including mlncRNA23, mlncRNA28 and mlncRNA30 were studied and the results indicated that they are differentially expressed in different tissues including roots, stems and leaves, with the highest expression levels in leaves. Moreover, the transcript levels of these genes affected by the cold and drought stresses. The results obtained from the present study is important in order to understand the potential role of mlncRNAs in digitalis plants, especially in response to abiotic stresses.

Cyclotides are small plant disulfide-rich and cyclic proteins with a diverse range of biological activities. Cyclotide-like genes show key sequence features of cyclotides and are present in the Poaceae. In this study the cDNA of the nine cyclotide-like genes were cloned and sequenced using 3′RACE from Zea mays. The gene expression of two of these genes (Zmcyc1 and Zmcyc5) were analyzed by real-time PCR in response to biotic (Fusarium graminearum, Ustilago maydis and Rhopalosiphum maydis) and abiotic (mechanical wounding, water deficit and salinity) stresses, as well as in response to salicylic acid and methyl jasmonate elicitors to mimic biotic stresses. All isolated genes showed significant similarity to other cyclotide-like genes and were classified in two separate clusters. Both Zmcyc1 and Zmcyc5 were expressed in all studied tissues with the highest expression in leaves and lowest expression in roots. Wounding, methyl jasmonate and salicylic acid significantly induced the expression of Zmcyc1 and Zmcyc5 genes, but the higher expression was observed for Zmcyc1 as compared with Zmcyc5. Expression levels of these two genes were also induced in inoculated leaves with F. graminearum, U. maydis and also in response to insect infestation. In addition, the 1000-base-pairs (bp) upstream of the promoter of Zmcyc1 and Zmcyc5 genes were identified and analyzed using the PlantCARE database and consequently a large number of similar biotic and abiotic cis-regulatory elements were identified for these two genes.

Feverfew (Tanacetum parthenium) is a medicinal plant belonging to the Asteraceae family. To improve understanding terpene metabolism in feverfew, the relative gene expression of four key genes coding 3-hydroxy-3-methylglutarylcoenzyme A reductase (HMGR) and germacrene A synthase (GAS) from the mevalonic acid pathway (MVA), as well as 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) and hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (HDR) from the methyl erythritol phosphate pathway (MEP), were examined. Target organs and tissues included young leaves (not fully expanded), mature leaves (fully expanded), flowers, stems, roots, and glandular trichomes. HMGR, DXR, and HDR were isolated and sequenced for the first time in feverfew. Real-time quantitative PCR analysis revealed differential expression of these genes in feverfew tissues and developmental stages.

Thyme (Thymus vulgaris L.) is known to produce a variety of phenolic monoterpenes such as thymol and carvacrol. Thymol and carvacrol are health-promoting, biocide and antitoxin compounds and have been considered as the main constituents of essential oils in T. vulgaris. To improve our understanding of the regulation of monoterpene biosynthesis in thyme, the expression of genes related to thymol and carvacrol biosynthesis in different tissues and in response to abiotic elicitors was analyzed. Methyl jasmonate (MeJA), salicylic acid (SA), trans-cinnamic acid (tCA) and UV-C irradiation were applied to T. vulgare leaves and transcript levels of early (DXR) and late (TvTPS1, CYP71D178 and CYP71D180) biosynthetic genes of thymol and carvacrol were measured. The results showed that early step and late step genes in thymol/carvacrol biosynthesis are differentially regulated. DXR was not found to be exclusively expressed in glandular trichomes; in contrast, biosynthetic genes including γ-terpinene synthase (TvTPS1) and two cytochrome P450s, CYP71D178 and CYP71D180, were preferentially expressed in glandular secretory trichomes. The high expression of late biosynthetic genes in glandular trichomes, which also contain the highest concentration of thymol and carvacrol, suggests that glandular trichomes are the structure in which thymol/carvacrol biosynthesis and accumulation occur. Our results indicate that in addition to abiotic elicitors, developmental and spatial factors also play a key role in the biosynthesis of thymol and carvacrol, most likely relating to glandular trichome density and/or activity. Hence optimization of these factors could be considered as a useful strategy to achieve high yield of valuable compounds in T. vulgare or other closely related plant species.

Morphological and biochemical responses of feverfew plants exposed to low (5 μM) and high (35 and 70 μM) levels of Cd or Cu were investigated. Increasing metal supply notably reduced the plant biomass. Elevated Cd and Cu levels also resulted in an increase in the leaf proline content. Besides, decrease in ascorbic acid (AsA) and glutathione (GSH) contents was similar in the leaves of Cd- and Cu-treated plants, indicating altered biosynthesis of AsA and GSH under metal excess. High metal doses stimulated increase in antioxidative enzyme activities that could be related to elevated hydrogen peroxide (H2O2) content and subsequent lipid peroxidation. Cd was typically more accumulated in shoots and roots than Cu, leading to higher translocation factor at high Cd doses. In terms of essential oil content, it seems that Cd had an inhibitory effect during the experiment, whereas Cu was found to stimulate it only at 5 μM. Furthermore, high Cd supply enhanced the relative proportion of monoterpene hydrocarbons, while Cu increased the proportion of sesquiterpenes, especially at 5 μM. This result provides the first evidence of the response of feverfew plants to Cd or Cu by associating stress-related responses with changes in terpenoids.

Feverfew (Tanacetum parthenium) is a medicinal herb which is rich in sesquiterpene lactones. The main sesquiterpene lactone in feverfew is parthenolide. Costunolide has been considered to be the immediate precursor of parthenolide. Parthenolide and costunolide levels in flowers and in leaves collected during the vegetative and generative phase of three feverfew genotypes (diploid, tetraploid and Zardband cv.) and in 2,4-D treated leaves of the diploid genotype were analyzed using UPLC–MS/MS. Parthenolide and costunolide levels showed a similar pattern in all genotypes, and were higher in flowers than in leaves. The developmental pattern of these two compounds was not the same in flowers of the different genotypes and 2,4-D treatment increased both coordinately. In conclusion, we show that genetical, developmental and spatial factors all influence the composition of sesquiterpene lactones in feverfew.

Background: Medicinal plants have been considered a good source for finding new pharmaceutical chemicals, and identification of chemical composition is the first step towards uncovering the nature of bioactive compounds. Objectives: The aim of this study was to analyze the composition of the essential oil of Ballota nigra subsp. kurdica from Iran for the first time and to test its in vitro antibacterial activity against some bacteria. Methods: The flowers of Ballota nigra subsp. kurdica were subjected to a Clevenger extractor for essential oil extraction, and gas chromatography mass spectrometry analysis was performed for its analysis. Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Bacillus subtilis, Klebsiella pneumonia and Pseudomonas aeruginosa bacteria were used to test antibacterial activity of the essential oil using the disk diffusion method. Results: GC-MS analysis detected 22 components in the extracted essential oil which constituted more than 98% of total essential oil. The main compounds of the oil were caryophyllene oxide (39.43%), trans-caryophyllene (24.88%), germacrene D (7.64%), 1-undecene (4.20%), isoaromadendrene epoxide (3.25%), and tridecane-1 (2.81%). The essential oil showed moderate to high antimicrobial activity against all tested strains. Conclusions: The data of this study suggests that the essential oil of B. nigra subsp. kurdica could be considered a natural antimicrobial agent to preserve food and treat infections in the near future.

Development of wheat-alien translocation lines will facilitate its practical utilization in wheat improvement. The objective of the present study was to produce compensating wheat--Thinopyrum bessarabicum whole arm Robertsonian translocations (RobTs) involving chromosomes 2B of wheat and 2E(b) of Th. bessarabicum through the mechanism of centric breakage-fusion. F2 population from crosses between DS2E(b)(2B) substitution line and bread wheat 'Roushan' (2n = 6x = 42, AABBDD) as female parent were made. Forty one F2 lines (L1 to L41) were screened for their chromosome composition. Three 2E(b) specific PCR-based Landmark Unique Gene (PLUG) markers were used for screening F2 progeny derived from plants double-monosomic for chromosome 2B and 2E(b). Two Rob Ts (-5%) were observed among F2 plants. Homozygous translocation (T2E(b)S.2BL) with good plant vigor and full fertility were selected from F3 families. The T2E(b)S.2BL stock has longer awn than that of its parents. It is cytogenetically stable, and may be useful in wheat improvement.

The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring (cv. Kohdasht) and two winter (cvs. Sardari and Norstar) cultivars of wheat (Triticum aestivum L.) exposed to 4°C. Plants were sampled on days 2, 14, 21 and 35 of exposure to 4°C. The final leaf number (FLN) was determined throughout the vernalization periods (0, 7, 14, 24, and 35 d) at 4°C. The final leaf number decreased until days 24 and 35 in Sardari and Norstar cultivars, respectively, indicating the vernalization saturation at these times. No clear changes were detected in the final leaf number of Kohdash cultivar, verifying no vernalization requirement for this spring wheat cultivar. Comparing with control, clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4°C-treatment in the leaves of the both winter wheat cultivars but, such response was not detected in the spring cultivar. However, the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences. With increasing exposure time to 4°C, the winter cultivars tended to produce more HMW polypeptides than the spring cultivar. Similar proteins were induced in both Sardari and Norstar winter wheat cultivars, however, the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement. These observations indicate that vernalization response regulates the expression of low temperature (LT) tolerance proteins and determines the duration of expression of LT-induced proteins.

Feverfew (Tanacetum parthenium) is a perennial medicinal herb and is a rich source of sesquiterpene lactones. Parthenolide is the main sesquiterpene lactone in feverfew and has attracted attention because of its medicinal potential for treatment of migraine and cancer. In the present work the parthenolide content in different tissues and developmental stages of feverfew was analyzed to study the timing and localization of parthenolide biosynthesis. The strongest accumulating tissue was subsequently used to isolate sesquiterpene synthases with the goal to isolate the gene encoding the first dedicated step in parthenolide biosynthesis. This led to the isolation and charachterization of a germacrene A synthase (TpGAS) and an (E)-beta-caryophyllene synthase (TpCarS). Transcript level patterns of both sesquiterpene synthases were analyzed in different tissues and glandular trichomes. Although TpGAS was expressed in all aerial tissues, the highest expression was observed in tissues that contain high concentrations of parthenolide and in flowers the highest expression was observed in the biosynthetically most active stages of flower development. The high expression of TpGAS in glandular trichomes which also contain the highest concentration of parthenolide, suggests that glandular trichomes are the secretory tissues where parthenolide biosynthesis and accumulation occur. (C) 2011 Elsevier Ltd. All rights reserved. Ministry of Sciences, Research and Technology of Iran; European Commission [227448]; IBOS-ACTS [053.63.305]

The anther culture response of Citrullus lanatus L. was studied to evaluate the effect of growth regulators and wheat ovary-conditioned medium in Charleston Gray cultivar and the effect of temperature pretreatment in Crimson sweet cultivar. Callus-mediated embryogenesis was induced on Murashige and Skoog (MS) medium supplemented with 2, 4-dichlorophenoxyacetic acid (2,4-D) and a-naphthaleneacetic acid alone as well as 2,4-D in combination with N6-benzylaminopurine/kinetin (BAP/KN). Optimal percentage of embryogenic calli (EC) and mean number of embryos per anther (ME/A) were induced on MS medium supplemented with 2.0 µM 2, 4-D and 1.5 µM BAP in cultivar of Charleston Gray. In this cultivar, the inclusion of 10 wheat ovaries in the induction medium significantly increased the percentage of EC and ME/A up to 2.5- and 3-fold when compared with that in the control, respectively. Low-temperature pretreatment of flower buds (4 °C for 2 and 5 days) and cultured anthers (4 °C for 4 and 8 days) were tested in Crimson sweet cultivar and best response in terms of %EC and ME/A was obtained with pretreatment of cultured anthers at 4 °C for 4 days and flower buds at 4 °C for 2 days. Also, heat pretreatments of the cultured anthers at 30 °C for 7 and 32 °C for 2 days produced the highest percentage of EC compared to control and other heat pretreatments in Crimson sweet cultivar. The highest frequency of ME/A was obtained from cultured anthers incubated at 32 °C for 2 days. Embryos germinated into plantlets on MS medium containing 2.22 µM BAP, 3 % sucrose, and 0.8 % agar. The root tips of 12 regenerated plantlets were analyzed for ploidy level, of which 10 have been haploids.

The sesquiterpene costunolide has a broad range of biological activities and is the parent compound for many other biologically active sesquiterpenes such as parthenolide. Two enzymes of the pathway leading to costunolide have been previously characterized: germacrene A synthase (GAS) and germacrene A oxidase (GAO), which together catalyse the biosynthesis of germacra-1(10),4,11(13)-trien-12-oic acid. However, the gene responsible for the last step toward costunolide has not been characterized until now. Here we show that chicory costunolide synthase (CiCOS), CYP71BL3, can catalyse the oxidation of germacra-1(10),4,11(13)-trien-12-oic acid to yield costunolide. Co-expression of feverfew GAS (TpGAS), chicory GAO (CiGAO), and chicory COS (CiCOS) in yeast resulted in the biosynthesis of costunolide. The catalytic activity of TpGAS, CiGAO and CiCOS was also verified in planta by transient expression in Nicotiana benthamiana. Mitochondrial targeting of TpGAS resulted in a significant increase in the production of germacrene A compared with the native cytosolic targeting. When the N. benthamiana leaves were co-infiltrated with TpGAS and CiGAO, germacrene A almost completely disappeared as a result of the presence of CiGAO. Transient expression of TpGAS, CiGAO and CiCOS in N. benthamiana leaves resulted in costunolide production of up to 60 ng.g(-1) FW. In addition, two new compounds were formed that were identified as costunolide-glutathione and costunolide-cysteine conjugates.

An efficient colchicine-mediated chromosome doubling of diploid feverfew followed by the morphophenological, physiological, phytochemical, and cytological changes of the obtained tetraploid plants was conducted. One-week-old seedlings of feverfew were treated with 0.05% (w/v) colchicine for 2, 4, 6, 8, and 24 h. Tetraploid plants were regenerated after 4 months, showing significant changes in stomatal size and density; sizes of seed; flower, pollen, leaf, trichome, cell, nucleus, and parthenolide content; chromosome number; ploidy level; chlorophyll content index; and quantum efficiency of photosystem II. Such characteristics of induced tetraploid feverfews can be useful in medicinal and ornamental applications, e.g., the study of flower morphogenesis, trichome differentiation, and parthenolide biosynthesis. The increase in parthenolide in tetraploids of the next generation (selfed T0 plants) showed that ploidy induction is a good breeding method for feverfew.