7 research outputs found

    Impact du relief et des circuits semenciers locaux sur la diversité agro-morphologique du blé dur (Triticum turgidum ssp. durum) dans la vallée d'Er Rich à Imilchil (Maroc)

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    Phenotypic diversity of 101 durum wheat landrace populations collected from the oasis of the Oriental Atlas Mountains (Morocco) was studied. Nine characters (morphological and agronomic) were measured on the 3030 lines (30 lines per population). The frequencies of each phenotypic class were used for the estimate and the analysis of diversity, by considering the geographical zones of origin and the gradients of altitude. The Shannon-Weaver diversity index (H’) showed a wide variability for all considered traits. This index varies from one area to another and from one altitudinal class to another. The mean H’ recorded for all areas was 0.62, indicating the presence of a high degree of polymorphism among the studied durum wheat landrace populations. The results of the multiple component analysis and the hierarchical clustering showed that the geographical proximity and altitude play a main function in the discrimination and the structure of the studied durum wheat populations. The information gathered from this study could be used in conventional breeding programs and in situ conservation of the diversity. La diversitĂ© phĂ©notypique de 101 populations locales de blĂ© dur issues des oasis de montagnes de l’Atlas oriental (Maroc) a Ă©tĂ© Ă©tudiĂ©e. Neuf caractères (morphologiques et agronomiques) ont Ă©tĂ© mesurĂ©s sur les 3030 lignĂ©es (30 lignĂ©es par population). Les frĂ©quences de chaque classe phĂ©notypique ont Ă©tĂ© utilisĂ©es pour l’estimation et l’analyse de la diversitĂ©, en considĂ©rant les zones gĂ©ographiques d’origine et les gradients d’altitude. L’indice de diversitĂ© de Shannon-Weaver (H’) a montrĂ© une forte variabilitĂ© pour l’ensemble des caractères considĂ©rĂ©s. Cet indice varie d’une zone Ă  une autre et d’une classe d’altitude Ă  une autre. Le H’ moyen obtenu pour l’ensemble des zones est de 0,62, indiquant la prĂ©sence d’un degrĂ© Ă©levĂ© de polymorphisme au sein des populations locales de blĂ© dur collectĂ©es. Les rĂ©sultats de l’analyse en composantes multiples ainsi que de la classification hiĂ©rarchique ont montrĂ© que la proximitĂ© gĂ©ographique et l’altitude jouent un rĂ´le majeur dans la discrimination ainsi que sur la structuration des populations de blĂ© dur Ă©tudiĂ©es. Les informations recueillies Ă  partir de ces rĂ©sultats peuvent ĂŞtre exploitĂ©es dans des programmes de sĂ©lection conventionnels et de conservation in situ de la diversitĂ©. Mots clĂ©s: Populations locales, diversitĂ© phĂ©notypique, structuration, conservation in situ, blĂ© dur (Triticum turgidum ssp. durum)

    Impact du relief et des circuits semenciers locaux sur la diversité agro-morphologique du blé dur (Triticum turgidum ssp. durum) dans la vallée d’Er Rich – Imilchil (Maroc)

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    Phenotypic diversity of 101 durum wheat landrace populations collected from the oasis of the Oriental Atlas Mountains (Morocco) was studied. Nine characters (morphological and agronomic) were measured on the 3030 lines (30 lines per population). The frequencies of each phenotypic class were used for the estimate and the analysis of diversity, by considering the geographical zones of origin and the gradients of altitude. The Shannon-Weaver diversity index (H’) showed a wide variability for all considered traits. This index varies from one area to another and from one altitudinal class to another. The mean H’ recorded for all areas was 0.62, indicating the presence of a high degree of polymorphism among the studied durum wheat landrace populations. The results of the multiple component analysis and the hierarchical clustering showed that the geographical proximity and altitude play a main function in the discrimination and the structure of the studied durum wheat populations. The information gathered from this study could be used in conventional breeding programs and in situ conservation of the diversity

    Anchoring durum wheat diversity in the reality of traditional agricultural systems: varieties, seed management, and farmers’ perception in two Moroccan regions

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    Background: Traditional agrosystems are the places were crop species have evolved and continue to evolve under a combination of human and environmental pressures. A better knowledge of the mechanisms underlying the dynamics of crop diversity in these agrosystems is crucial to sustain food security and farmers’ self-reliance. It requires as a first step, anchoring a description of the available diversity in its geographical, environmental, cultural and socio-economic context. [br/] Methods: We conducted interviews with farmers cultivating durum wheat in two contrasted traditional agrosystems of Morocco in the Pre-Rif (163 farmers) and in the oases of the Atlas Mountains (110 farmers). We documented the varietal diversity of durum wheat, the main characteristics of the farms, the farming and seed management practices applied to durum wheat, and the farmers’ perception of their varieties. [br/] Results: As expected in traditional agrosystems, farmers largely practiced diversified subsistence agriculture on small plots and relied on on-farm seed production or informal seed exchange networks. Heterogeneity nevertheless prevailed on many variables, especially on the modernization of practices in the Pre-Rif region. Fourteen (resp. 11) traditional and 5 (resp. 3) modern varieties were identified in the Pre-Rif region (resp. in the Atlas Mountains). The majority of farmers grew a single variety, and most traditional varieties were distributed in restricted geographical areas. At the farm level, more than half of the varieties were renewed in the last decade in the Pre-Rif, a more rapid renewal than in the Atlas Mountain. Modern varieties were more prevalent in the Pre-Rif region and were integrated in the traditional practices of seed production, selection and exchange. They were clearly distinguished by the farmers from the landraces, the last ones being appreciated for their quality traits. [br/] Conclusions: The surveyed traditional agrosystems constitute open, dynamic and heterogeneous entities. We suggest that competing factors could favour or limit the cultivation of improved varieties and the erosion of original durum wheat diversity. This first description opens the way to focused further investigations, including complementing variety names with cultural, genetic and phenotypic information and unravelling the multidimensional factors and consequences of modern variety adoption

    Diversité agro-morphologique et gestion variétale par les agriculteurs du blé dur (Triticum turgidum ssp. durum) dans le Pré-Rif marocain

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    Le blé dur est une culture stratégique au Maroc. La caractérisation et l’évaluation des variétés cultivées dans différents agro-écosystèmestraditionnels permettent la sauvegarde et la réhabilitation de ce patrimoine génétique ainsi que son utilisation dans desprogrammes de sélection. Dans ce contexte, une collection de 59 populations traditionnelles de blé dur issues de la région du Pré-Rif a été étudiée en utilisant neuf traits agro-morphologiques. La diversité phénotypique a été déterminée par l’indice de diversitéShannon-Weaver (H’) à différents niveaux (Totalité de l’échantillon, par typologie du blé et par nom variétal). Les H’ estimés ontmontré une large variabilité phénotypique pour les différents traits avec un H’ moyen de 0,78. Les résultats de l’analyse des correspondancesmultiples et de la classification hiérarchique ont montré une nette distinction entre les variétés modernes et traditionnelles.Les caractères agro-morphologiques ne permettent pas de différencier les variétés traditionnelles entre elles. Les résultats de ce travailont permis de révéler la grande diversité phénotypique des variétés de blé dur qui ne correspond que partiellement aux noms desvariétés du fait de l’existence d’homonymes et de synonymes dans les noms donnés par les agriculteurs.Durum wheat is a strategic crop in Morocco. Characterization and evaluation of cultivated varieties in different traditional agroecosystemsallows safeguard and rehabilitation of this genetic heritage and its use in breeding programs. In this context, a collectionof 59 traditional populations of durum wheat from the Pre-Rif region was studied using nine agro-morphological traits. Phenotypicdiversity was determined by the Shannon-Weaver diversity index (H’) at different levels (totality of sample, by type of wheat andvarietal names). Estimated H’ showed a wide genetic variability for different traits with a mean of H’=0.78. The results of the multiplecorrespondence analysis and hierarchical clustering showed a clear distinction between modern and traditional varieties. In traditionalvarieties, agro-morphological traits do not differentiate between varieties. The results of this work revealed the great phenotypic andnominative diversity of durum wheat varieties as well as the existence of homonyms and synonyms in the names given by farmers

    A new orally bioavailable dual adenosine A2B/A3 receptor antagonist with therapeutic potential.

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    The synthesis and SAR of 5-heterocycle-substituted aminothiazole adenosine receptor antagonists is described. Several compounds show high affinity and selectivity for the A2B and A3 receptors. One compound (5f) shows good ADME properties in the rat and as such may be an important new compound in testing the current hypotheses proposing a therapeutic role for a dual A2B/A3 antagonist in allergic diseases

    The Discovery And Optimisation of 4-(8-(3-Fluorophenyl)-1,7-naphthyridin-6-yl)cyclohexanecarboxylic acid, An Improved PDE4 Inhibitor For The Treatment of COPD.

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    Herein we describe the optimisation of a series of PDE4 inhibitors, with special focus on solubility and pharamcokinetics, to clinical compound 2, 4-(8-(3-fluorophenyl)-1,7-naphthyridin-6-yl)cyclohexanecarboxylic acid. Compound 2 was found to have exemplary pharmacokinetics in humans, which enabled a novel dosing regime and the achievement of high plasma drug levels without associated nausea or emesis

    Solubility-Driven Optimisation of Phosphodiesterase-4 Inhibitors Leading to a Clinical Candidate

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    The solubility-driven optimisation of a series of 1,7-napthyridine phosphodiesterase 4 inhibitors is described. Directed structural changes resulted in increased aqueous solubility, enabling superior pharmacokinetic properties, with retention of PDE4 inhibition. A range of potent and orally bioavailable compounds with good in vivo efficacy in animal models of inflammation and reduced emetic potential compared to previously described drugs were synthesised. Compound 2d was taken forward as a clinical candidate for the treatment of COPD
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