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1.
Food Chem ; 307: 125521, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655264

RESUMO

The essential oils and antioxidant activity of four Thymus species were evaluated under five light spectra (namely, red, blue, red-blue, white, and greenhouse condition). The highest essential oil yield (4.17%) was observed under red light in T. migricus, while the lowest (1.05%) was observed in T. carmanicus under greenhouse conditions. Light quality also led to difference in essential oil constituents. The highest thymol (66%) was found in T. migricus exposed to blue light, while the least (1.69%) was observed in T. kotschyanus grown under red-blue light. The LED treatments did not induce any significant effect on carvacrol of Thymus species in comparison to the greenhouse condition. Finally, the analysis of variance indicates that the effect of light varied with the studied species. T. migricus performed the highest antioxidant capacity (IC50 = 176.8 µg/mL) under blue light. Overall, essential oil components as well as antioxidants showed significant responses to light emitting diodes wavelengths.


Assuntos
Antioxidantes/metabolismo , Luz , Timol/metabolismo , Thymus (Planta)/química , Análise de Variância , Antioxidantes/química , Cromatografia Gasosa , Análise por Conglomerados , Efeito Estufa , Óleos Voláteis/química , Análise de Componente Principal , Timol/química , Thymus (Planta)/crescimento & desenvolvimento , Thymus (Planta)/metabolismo
2.
Phytochemistry ; 169: 112126, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31644985

RESUMO

Thyme (Thymus spp.) is a valuable genus of Lamiaceae family with different pharmaceutical and food properties. Thymol has also been considered as the major essential oil compound in most of the studied Thymus species. In this research, the gene encoding γ-terpinene synthase (Ttps2) was sequenced in T. vulgaris and in eight Iranian thymes including T. carmanicus, T. daenensis, T. fedtschenkoi, T. kotschyanus, T. migricus, T. pubescens, T. serpyllum, and T. trautvetteri. Genetic relationships based on terpene synthase genes were also determined among the studied species. Rapid Amplification of cDNA Ends (RACE) PCR was done to complete the sequence of all species. The cDNA of the studied species possessed an open reading frame ranging from 1788 to 1794 bp that encode for a protein of 596-598 amino acids, presenting all the conserved motifs characteristics of monoterpene synthases. The taxonomic status of Thymus species was determined based on eight reported sections. The species were classified in three major groups. The first and second group comprised species of Micantes and Mastichina sections. The third cluster included the species belonging to Serpyllum and Pseudothymbra sections. Overall, phylogenetic analysis according to whole sequence of Ttps2 gene can help providing insights in respect to its evolutionary process. Finally, clustering based on the amount of main essential oils components (thymol and carvacrol) was compared with that based on Ttps2 gene classification in the studied Thymus species, showing that clustering is not always in accordance.

3.
Sci Rep ; 9(1): 18626, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819118

RESUMO

Soil salinity is a global environmental challenge for crop production. Understanding the uptake and transport properties of salt in plants is crucial to evaluate their potential for growth in high salinity soils and as a basis for engineering varieties with increased salt tolerance. Positron emission tomography (PET), traditionally used in medical and animal imaging applications for assessing and quantifying the dynamic bio-distribution of molecular species, has the potential to provide useful measurements of salt transport dynamics in an intact plant. Here we report on the feasibility of studying the dynamic transport of 22Na in millet using PET. Twenty-four green foxtail (Setaria viridis L. Beauv.) plants, 12 of each of two different accessions, were incubated in a growth solution containing 22Na+ ions and imaged at 5 time points over a 2-week period using a high-resolution small animal PET scanner. The reconstructed PET images showed clear evidence of sodium transport throughout the whole plant over time. Quantitative region-of-interest analysis of the PET data confirmed a strong correlation between total 22Na activity in the plants and time. Our results showed consistent salt transport dynamics within plants of the same variety and important differences between the accessions. These differences were corroborated by independent measurement of Na+ content and expression of the NHX transcript, a gene implicated in sodium transport. Our results demonstrate that PET can be used to quantitatively evaluate the transport of sodium in plants over time and, potentially, to discern differing salt-tolerance properties between plant varieties. In this paper, we also address the practical radiation safety aspects of working with 22Na in the context of plant imaging and describe a robust pipeline for handling and incubating plants. We conclude that PET is a promising and practical candidate technology to complement more traditional salt analysis methods and provide insights into systems-level salt transport mechanisms in intact plants.

4.
Sci Rep ; 9(1): 7249, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31076605

RESUMO

Cultivation of salinity-tolerant crops can help mitigate salinization threats to soil and fresh water resources. This study was conducted to investigate the quantitative genetic basis of yield, yield components, and quality-related traits of salinity-stressed melon (Cucumis melo L.) using 55 melon hybrids and their 11 parents (half diallel). The results of combined ANOVA revealed highly significant effects of salinity and genotype on all the traits studied. Salinity stress influenced the inheritance of all the traits. The lower values of variance components (mainly additive), GCA/SCA ratio, as well as broad- and narrow-sense heritabilities were estimated for saline conditions (ECW = 14 dSm-1) when compared with those obtained under non-saline conditions. Fruit weight was governed by additive effects in non-saline conditions, but largely governed by the dominant nature in saline conditions. Based on the results obtained, especially as reflected by fruit yield, it is possible to develop melon hybrids with higher salinity tolerance than is currently observed in tolerant cultivars. On the other hand, most of the traits contributing to fruit quality are found to be governed by additive effects, allowing for their further improvement through recurrent selection to develop new cultivars of high yield and good quality for cultivation under saline conditions.

5.
Physiol Mol Biol Plants ; 24(1): 61-73, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29398839

RESUMO

Aegilops cylindrica, a salt-tolerant gene pool of wheat, is a useful plant model for understanding mechanism of salt tolerance. A salt-tolerant USL26 and a salt-sensitive K44 genotypes of A. cylindrica, originating from Uremia Salt Lake shores in Northwest Iran and a non-saline Kurdestan province in West Iran, respectively, were identified based on screening evaluation and used for this work. The objective of the current study was to investigate the expression patterns of four genes related to ion homeostasis in this species. Under treatment of 400 mM NaCl, USL26 showed significantly higher root and shoot dry matter levels and K+ concentrations, together with lower Na+ concentrations than K44 genotype. A. cylindrica HKT1;5 (AecHKT1;5), SOS1 (AecSOS1), NHX1 (AecNHX1) and VP1 (AecVP1) were partially sequenced to design each gene specific primer. Quantitative real-time PCR showed a differential expression pattern of these genes between the two genotypes and between the root and shoot tissues. Expressions of AecHKT1;5 and AecSOS1 was greater in the roots than in the shoots of USL26 while AecNHX1 and AecVP1 were equally expressed in both tissues of USL26 and K44. The higher transcripts of AecHKT1;5 in the roots versus the shoots could explain both the lower Na+ in the shoots and the much lower Na+ and higher K+ concentrations in the roots/shoots of USL26 compared to K44. Therefore, the involvement of AecHKT1;5 in shoot-to-root handover of Na+ in possible combination with the exclusion of excessive Na+ from the root in the salt-tolerant genotype are suggested.

6.
Food Chem ; 220: 153-161, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27855883

RESUMO

In this study, the essential oil (EO) composition, flavonoid and phenolic contents, and antioxidant activities of fourteen Thymus accessions belonging to ten species were evaluated. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of 38 compounds with the major constituents including thymol (12.4-79.74%), carvacrol (4.37-42.14%), geraniol (0.3-22.44%), and p-cymene (0.8-12.86%). Cluster analysis identified three groups of high thymol, geraniol/linalool, and high carvacrol. The highest phenolic and flavonoid contents were detected in T. daenensis-1 (70.6mg tannic acid equivalents (TAE) g-1 DW) and T. vulgaris (8.55mg quercetin equivalents (QE) g-1 DW), respectively. The antioxidant activities of the samples were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power assay. The results demonstrated that T. daenensis-3 (IC50=273.36), T. vulgaris (IC50=289.3), and T. fedtschenkoi-3 (IC50=339.22) possessed higher antioxidant activities than the others. Finally, the Thymus species with high bioactive compounds may be recommended for further food applications.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Óleos Voláteis/química , Fenóis/análise , Thymus (Planta)/química , Análise por Conglomerados , Cromatografia Gasosa-Espectrometria de Massas , Irã (Geográfico) , Modelos Lineares , Monoterpenos/análise , Extratos Vegetais/análise , Análise de Componente Principal , Taninos/análise , Terpenos/análise , Timol/análise , Thymus (Planta)/classificação
7.
Plant Sci ; 251: 128-138, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27593471

RESUMO

The emerging model Setaria viridis with its C4 photosynthesis and adaptation to hot and dry locations is a promising system to investigate water use and abiotic stress tolerance. We investigated the physiological plasticity of six S. viridis natural accessions that originated from different regions of the world under normal conditions and conditions of water-deficit stress and high temperatures. Accessions Zha-1, A10.1 and Ula-1 showed significantly higher leaf water potential (Ψleaf), photosynthesis (A), transpiration (E), and stomatal conductance (gs) rates compared to Ast-1, Aba-1 and Sha-1 when grown under stress conditions. Expression analysis of genes associated with C4 photosynthesis, aquaporins, ABA biosynthesis and signaling including genes involved in stress revealed an increased sensitivity of Ast-1, Aba-1 and Sha-1 to stresses. Correlation analysis of gene expression data with physiological and biochemical changes characterized A10.1 and Ast-1 as two extreme tolerant and sensitive accessions originated from United States and Azerbaijan under water-deficit and heat stress, respectively. Although preliminary, our study demonstrated the plasticity of S. viridis accessions under stress, and allows the identification of tolerant and sensitive accessions that could be use to study the mechanisms associated with stress tolerance and to characterize of the regulatory networks involved in C4 grasses.


Assuntos
Setaria (Planta)/fisiologia , Estresse Fisiológico , Água/metabolismo , Ácido Abscísico/biossíntese , Adaptação Fisiológica , Genótipo , Resposta ao Choque Térmico , Temperatura Alta , Fotossíntese , Estômatos de Plantas/fisiologia , Transpiração Vegetal , Setaria (Planta)/genética , Setaria (Planta)/metabolismo , Transdução de Sinais
8.
Iran J Biotechnol ; 13(1): 17-25, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28959277

RESUMO

BACKGROUND: Pomegranate fruit (Punica granatum L.) is a rich source of anthocyanin pigments resulting in vibrant colours and anti-oxidant contents. Although the intensity and pattern of anthocyanin biosynthesis in fruit are strongly influenced by R2R3-MYB transcription factors, little is known about the regulation and role of MYB in anthocyanin pathway of pomegranate. OBJECTIVES: The present study was conducted to elucidate the relationship between the expression of MYB transcription factor and the anthocyanin accumulation during the colour development phase of pomegranate fruits. MATERIALS AND METHODS: In this work, R2R3-MYB transcription factor (PgMYB) was isolated and characterized from pomegranate skin through RACE-PCR. The expression of PgMYB gene was monitored in three distinct pomegranate accessions with distinctive skin colour and pattern by semi-quantitative RT-PCR. RESULTS: The results indicated a strong association between skin colour in mature pomegranate fruits with the PgMYB transcripts. The highest expression level of PgMYB gene was observed in Poost Siyah Yazd (dark purple skin) throughout the ripening process. Furthermore, comparison of PgMYB amino acid sequences with those of R2R3-MYB family in grapevine, eucalyptus, peach, cacao, populus and Arabidopsis demonstrated that this protein shares high similarity (75-85% amino acid identity) with their conserved MYB domain. Computational structure prediction of PgMYB showed that the three conserved amino acids (Asn, Lys and Lys) are present in the same position of the MYB domain. CONCLUSIONS: It is speculated that PgMYB gene influences the fruit colour and could be used to improve the accumula-tion of anthocyanin pigments in the pomegranate fruit.

9.
Int J Mol Sci ; 12(4): 2664-77, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21731465

RESUMO

Safflower (Carthamus tinctorious L.) is an oilseed crop that is valued as a source of high quality vegetable oil. The genetic diversity of 16 safflower genotypes originated from different geographical regions of Iran and some with exotic origin were evaluated. Eight different seed quality-related traits including fatty acid composition of seed oil (stearic acid, palmitic acid, oleic acid and linoleic acid), the contents of, oil, protein, fiber and ash in its seeds, as well as 20 inter-simple sequence repeat (ISSR) polymorphic primers were used in this study. Analysis of variance showed significant variation in genotypes for the seed quality-related traits. Based on ISSR markers, a total of 204 bands were amplified and 149 bands (about 70%) of these were polymorphic. Cluster analysis based on either biochemical or molecular markers classified the genotypes into four groups, showing some similarities between molecular and biochemical markers for evaluated genotypes. A logical similarity between the genotype clusters based on molecular data with their geographical origins was observed.


Assuntos
Carthamus tinctorius/genética , Variação Genética , Análise de Variância , Análise por Conglomerados , Primers do DNA/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Genótipo , Repetições de Microssatélites , Óleos Vegetais/análise , Reação em Cadeia da Polimerase , Polimorfismo Genético , Sementes/metabolismo
10.
J Genet ; 89(4): 401-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21273690

RESUMO

Meiotic restitution is considered to be a common mechanism of polyploidization in plants and hence is one of the most important processes in plant speciation. Meiotic behaviour of plant chromosomes is influenced by both genetic and environmental factors. In this study, the meiotic behaviour of cereal crops was investigated, which includes tetraploid wheat genotypes (with and without the meiotic restitution trait) and their derivates (synthetic hexaploid wheats and a doubled haploid (DH) line), grown at two planting dates in the field. In addition, two local landraces of emmer wheat (Triticum turgidum ssp. dicoccum), one wheat cultivar (Chinese spring), one DH triticale cultivar (Eleanor) and one rye accession were included. Immature spikes of mid-autumn and end-winter sowing plants were collected in April and May 2008, respectively, fixed in Carnoy's solution and stained with hematoxylin. Pollen mother cells (PMCs) from anthers at different stages of meiotic process were analysed for their chromosomal behaviour and irregularities. Meiotic aberrations such as laggards, chromosome bridges, micronuclei, abnormal cytokines, chromatin pulling and meiotic restitution were observed and the studied genotypes were accordingly ranked as follows: triticale > synthetic hexaploid wheats > tetraploid wheats possessing meiotic restitution > tetraploid wheats lacking meiotic restitution > rye. The results indicated that the samples that had been planted in the autumn, thus experiencing an optimum temperature level at the flowering stage, exhibited less meiotic irregularities than winter planting samples that encountered heat stress at the flowering period.


Assuntos
Temperatura Alta , Meiose/genética , Poliploidia , Triticum/genética , Cromossomos de Plantas , Genótipo , Haploidia , Pólen/genética , Estações do Ano , Secale/genética
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