13 research outputs found

    Assesment of molecular diversity of internal transcribed spacer region in some lines and landrace of Persian clover (Trifolium resupinatum L.)

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    &nbsp;Clover which is an herbaceous, annual, and self-pollinated plant belongs to fabaceae family (legumes) and has become naturalized in Iran, Asia Minor and the Mediterranean eastern suburban countries. The aim of the present study is ITS molecular evaluation of the nuclear ribosomal genes of lines and landraces of Persian Clover. The sequences were aligned using ClustalW method and by MegAlign software and the dendrogram of different phylogenetic and matrix relationships between the sequences were drawn. The results showed little genetic diversity between the lines and the landrace. The conserved sequence of the analyzed gene in the Persian clover is 561 base. Totally, 740 loci (69 and 671 loci, respectively, with and without removal and addition), 9 Singletons, and 5 haplotypes were identified. The highest rate of transfer was observed in pyrimidine (%16.3). The numerical value of the ratio (dN/dS) was 0.86, and since it was less than 1, the pure selection on the studied gene happened. The lines and landraces were not separated based on their geographic locations. In general, the results indicated that the highest rate of the regional diversity belonged to the clover plants in Lorestan region. Moreover, ITS markers did not seem suitable enough for evaluating the intra- species genetic variation, but it was quite well- suited for inter-species or intergeneric evaluation. The nanotechnology is a relatively new technology that has recently entered the field of agriculture. Nanotechnology covers the integration or manipulation of individual atoms, molecules or molecular masses to a diverse array of structures allowing the production of new characteristics and traits of interest. The aim of this study was to evaluate the effects of foliar application of TiO2 nanoparticles on quantitative traits (plant height, number of branches, dry weight of shoots and roots) and the essential oil content of thyme under different levels of field capacity. Our results showed that the application of TiO2 nanoparticles had significant effects on thyme growth, while the essential oil concentrations not affected. These results imply that the application of TiO2 nanoparticles in plants increase agronomic value under reduced irrigation conditions but has not different significant on essential oil. Normal 0 false false false EN-GB X-NONE AR-SA <w:LsdException Locked="false" Priority="72" Name="Colorful List A

    Characterization of novel SSR markers in diverse sainfoin (Onobrychis viciifolia) germplasm

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    Background: Sainfoin is a perennial forage legume with beneficial properties for animal husbandry due to the presence of secondary metabolites. However, worldwide cultivation of sainfoin is marginal due to the lack of varieties with good agronomic performance, adapted to a broad range of environmental conditions. Little is known about the genetics of sainfoin and only few genetic markers are available to assist breeding and genetic investigations. The objective of this study was to develop a set of SSR markers useful for genetic studies in sainfoin and their characterization in diverse germplasm.Results: A set of 400 SSR primer combinations were tested for amplification and their ability to detect polymorphisms in a set of 32 sainfoin individuals, representing distinct varieties or landraces. Alleles were scored for presence or absence and polymorphism information content of each SSR locus was calculated with an adapted formula taking into account the tetraploid character of sainfoin. Relationships among individuals were visualized using cluster and principle components analysis. Of the 400 primer combinations tested, 101 reliably detected polymorphisms among the 32 sainfoin individuals. Among the 1154 alleles amplified 250 private alleles were observed. The number of alleles per locus ranged from 2 to 24 with an average of 11.4 alleles. The average polymorphism information content reached values of 0.14 to 0.36. The clustering of the 32 individuals suggested a separation into two groups depending on the origin of the accessions.Conclusions: The SSR markers characterized and tested in this study provide a valuable tool to detect polymorphisms in sainfoin for future genetic studies and breeding programs. As a proof of concept, we showed that these markers can be used to separate sainfoin individuals based on their origin

    Caracterização morfológica, molecular e quimica de Arbutus unedo L. com vista à selecção de genótipos de superior qualidade

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    O medronheiro (Arbutus unedo L.) é uma árvore fruteira de elevado valor ornamental, ambiental, económico e medicinal devido às propriedades atribuídas às flores, frutos e folhas. No entanto, nos últimos anos não tem sido atribuída a devida importância a esta espécie na região de Trás-os-Montes, ao contrário do que se verifica no resto do país, registando-se um declínio da área ocupada por A. unedo nesta região. Com o objectivo de preservar e potenciar a produção desta espécie procedeu-se, numa primeira fase, à avaliação da diversidade de 4 populações naturais de A. unedo do interior Norte e Centro de Portugal, através da caracterização morfológica e molecular. Numa segunda fase, avaliaram-se as propriedades químicas de 19 genótipos provenientes da região de Bragança, com vista a seleccionar os de superior qualidade. Desta forma espera-se contribuir para a multiplicação e valorização de populações de maior interesse. A diversidade de populações naturais de A. unedo foi avaliada através da análise morfológica e genética pela utilização de marcadores moleculares, num total de 46 genótipos. Para tal, foram colhidas 40 folhas aleatoriamente em cada árvore, nas quais se mediu o comprimento, largura, peso seco, comprimento do pedúnculo e se estimou a relação comprimento/largura. Na análise genética utilizaram-se dois marcadores moleculares, amplificação aleatória de DNA polimórfico (RAPD) e sequencias simples repetidas (ISSR). As características morfológicas analisadas, e em especial o peso seco e comprimento do pedúnculo das folhas, permitiram diferenciar os vários genótipos. Os resultados decorrentes da análise genética mostraram que a população de Bragança foi a que apresentou maior diversidade genética (Na=1,93; Ne=1,71; Ho=0,39; Io=0,5; P=93,02), e Castelo Branco foi a que apresentou menor diversidade (Na=1,43; Ne=1,29; Ho=0,16; Io=0,24; P=43,02). Cada população foi caracterizada como um "pool" génico distinto, com baixa variabilidade intrapopulacional e com um grau de diferenciação bastante elevado. Este resultado sugere a necessidade de se proceder à conservação de cada população individualmente. O teste de Mantel evidenciou a inexistência de correlação entre as matrizes de distância calculadas com base nos marcadores RAPD e ISSR bem como entre estes e os dados morfológicos. vii A avaliação da actividade antioxidante, foi testada em extractos aquosos das folhas de 19 genótipos de A. unedo, pelos métodos do Poder Redutor e efeito bloqueador de radicais livres DPPH. O teor em fenóis totais foi avaliado pelo método de Folin-Ciocalteau. Os extractos provenientes das amostras de Vila Verde e Donai foram os que apresentaram maior actividade antioxidante (EC50 de 0,233 e 0,245 mg/ml para o poder redutor e 0,088 e 0,090 mg/ml para o DPPH), enquanto que a amostra proveniente de Vila Boa 2 foi aquela que apresentou maiores valores de EC50 (0,378mg/mL para o poder redutor e 0,142 mg/mL para o DPPH) revelando assim menor potencial antioxidante. Relativamente ao teor em fenóis totais a amostra de Bragança 1 foi a que reportou maior valor (215,0 mg. Equivalentes de acido gálico/g extracto) e a amostra de Vila Boa 4 a que apresentou o menor valor (148,0 mg. Equivalentes de acido gálico/g extracto).The strawberry tree (Arbutus unedo L.) is a fruit tree with high ornamental, environmental, economical and medicinal value due to the attributed properties to the flowers, fruits and leaves. However, in the last years, in Trás-os-Montes region, the deserved importance is not been given to this species, contrarily to what happens elsewhere in the country, being registered a decline in the area occupied by A. unedo in this region. In order to preserve and enhance the production of the species, in a first stage was proceeded the evaluation of the diversity of the 4 natural populations of the A. unedo from the North interior and Centre of Portugal, through morphological and molecular characterization. In a second phase, were evaluated the chemical proprieties of 19 genotypes belonging to Bragança district with the aim to select those of superior quality. Thus, we expect to contribute for the multiplication and valorization of the population with major interest. The diversity of the A. unedo natural populations was evaluated through the morphologic and molecular analysis, in a total of 46 genotypes. For such, 40 leaves were randomly collected from each tree, in which were measured the leave length and width, dry weight, peduncle length and leave length/width ratio. In the molecular analysis, were used two molecular markers, RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter-Simple Sequence Repeat). The morphological characteristics, specially the dry-weight and the peduncle length, allowed differentiating the various genotypes evaluated. The results obtained from molecular analysis shown that the population of Bragança presents higher genetic diversity (Na=1.93; Ne=1.71; Ho=0.39; Io=0.5; P=93.02), and Castelo Branco was the one that presents lowest diversity (Na=1.43; Ne=1.29; Ho=0.16; Io=0.24; P=43.02). Each population was characterized as a distinct genetic pool, with low intrapopulational variability and with a high level of differentiation. This result suggests that the populations should be conserved separately. The Mantel test showed the inexistence of correlation between the distances matrices calculated in basis on the RAPD and ISSR markers, as well as between this molecular markers and morphological data. The evaluation of the antioxidant activity was tested in aqueous extracts of the leaves of the 19 genotypes of A. unedo, by the reducing power and scavenging effect on the free radicals of DPPH. Total phenols content was assessed through the Folin-Ciocalteau method. The extracts from Vila Verde and Donai genotypes were those who ix reported higher antioxidant activity (EC50 values of 0.233 and 0.245 mg/mL for the reducing power method respectively, and 0.088 and 0.090 mg/mL for the DPPH method respectively), while the genotype from Vila Boa 2 was the one that reported higher EC50 values (0.378 and 0.142 mg/mL for the reducing power and DPPH methods respectively) and consequently lower antioxidant activity. Concerning total phenols, Bragança 1 genotype reported higher content (215.0 mg GAE/g of extract) and the genotype from Vila Boa 4 reported the lowest values (148.0 mg GAE/g of extract)

    Plant Biodiversity and Genetic Resources

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    The papers included in this Special Issue address a variety of important aspects of plant biodiversity and genetic resources, including definitions, descriptions, and illustrations of different components and their value for food and nutrition security, breeding, and environmental services. Furthermore, comprehensive information is provided regarding conservation approaches and techniques for plant genetic resources, policy aspects, and results of biological, genetic, morphological, economic, social, and breeding-related research activities. The complexity and vulnerability of (plant) biodiversity and its inherent genetic resources, as an integral part of the contextual ecosystem and the human web of life, are clearly demonstrated in this Special Issue, and for several encountered problems and constraints, possible approaches or solutions are presented to overcome these

    European landraces: on-farm conservation, management and use

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    This technical bulletin first establishes the context of European landrace diversity conservation and use; it reviews how landrace inventories can be generated, using practical examples of such inventories for European countries; it then provides specific case studies of the on farm management of landraces; and exemplars of how landrace use has been and might be further promoted within a European agricultural context. The recent introduction of the Commission Directive 2008/62 EC on Conservation Varieties will impact European landrace diversity; this is discussed together with the development of diverse European and National policies to support the conservation and use of landraces in production systems for sustainable agriculture. The technical bulletin concludes with a discussion of why we still need landraces, the current conservation status of European landraces, a review of the threats to on farm management of landraces and the opportunities for future landrace cultivation. It concludes with a proposal for a European on farm conservation and landrace management strategy that will both ensure the systematic conservation landrace diversity and promote its sustainable use, thus helping to underpin European food security and well being
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