Suchergebnisse

National audience ; The olive tree is the cultivated form of the wild oleaster, both of which belong to the subspecies europaea of Olea europaea and are naturally distributed all around the Mediterranean Sea. In addition to these, some trees escaped from cultivation resemble oleasters by their physiognomy. No specific morphologic marker unambiguously differentiates the three forms. Olive cultivars today show a wide diversity in their morphology and phenology. Olives are important economically in Mediterranean countries, and olive oils carrying the taste and aroma of the fruit are the base of a new gastronomy also economically significant. Olive trees fashion landscapes and prevent erosion, and a social culture is associated with their products. Oleasters are endangered due to recurrent gene flow from the olive tree, human impact on forests and climate change. Olive cultivars result from a long process of selection in diverse environments that have had different cultural practices and traditions ever since the olive tree began accompanying human migration in the Neolithic period. The first domestication had occurred by -5800 B.P. around the eastern Mediterranean basin. Olive cultivars are deeply differentiated according to ultimate use — for oil, table or mixed. Their origins are unknown and the country of origin is only an indication of where they come from. Cultivars and oleasters are wind-pollinated and outcrossing is the rule. Molecular markers have recently made it possible to study the diversity of olive trees and thus to attempt to verify myths and beliefs about their origins. Relations between cultivars can now be established with several types of markers. Domestication events must have appeared in several sites around eastern and western Mediterranean localities since cultivars have inherited cytotypes of local oleasters, and this probably occurred simultaneously. Human migrations displaced cultivars, leading to gene flow: local oleasters generate new forms and new cultivated genotypes. Cytoplasmic markers show at least four separate origins of olive trees from oleasters, and SSRs show at least seven. Molecular markers have enabled us to show that each cultivar corresponds to one clone with a few exceptions. This means that cultivars were propagated from a single tree, with some exceptions that may be due to mixing two or three sister progenies of one tree. Although oleasters originate from seven different refuge areas, gene flow caused by cultivar displacement has disturbed this structure. Some cultivars also have their origin in some of these primary populations but others appeared as hybrids between two or three of these zones. This suggests that gene flow occurred between local oleasters and cultivars introduced by human migrations ; De l'olivier à l'oléastre : origine et domestication de l'Olea europaea L. dans le Bassin méditerranéen Keywords : VEGETAL PRODUCTIONS, NATURAL RESOURCES AND ENVIRONMENTRésumé : L'olivier occupe la 24 e place des 35 espèces les plus cultivées dans le monde. La diversité phénologique des cultivars est remarquable et l'intérêt économique de l'espèce est majeur. Pourtant peu d'études ont porté sur la domestication de l'olivier et sur les relations entre l'olivier et sa forme sauvage, l'oléastre. Les marqueurs moléculaires rendent possible l'étude de la structure génétique des cultivars, des flux géniques et des relations entre la forme cultivée et sauvage. L'analyse de la diversité actuelle de la sous-espèce europaea d'Olea europea permet de remonter le temps et d'analyser les mécanismes qui ont conduit à cette diversité. Les processus utilisés donnent un panorama de la diversité après les glaciations et permettent de situer globalement les zones refuges qui apparaissent nombreuses et génétiquement très structurées. La comparaison avec la connaissance populaire montre que, chez cette espèce, l'histoire a été enjolivée, probablement pour combler l'absence de données historiques. L'origine de l'olivier à partir de l'oléastre ne fait plus de doute à l'est comme à l'ouest de la mer Méditerranée. Cependant, la diversité de l'oléastre et de l'olivier est maximale à l'ouest. L'archéologie confirmant la présence de l'oléastre à l'ouest, l'origine de la sous-espèce europaea est donc à reconsidérer

National audience ; Existing food aid programs have failed to prevent insufficient dietary intakes and micronutrient deficiencies in the population of homeless in Paris. To improve these programs, we designed a fortified food easy to consume in the street. Its economic interest was estimated by linear programming.We further tested its acceptability among the target population. A chocolate-flavoured spread naturally rich in potassium and n-3 fatty acids was fortified with calcium, zinc, vitamins C, D, E, B12, thiamine, niacin and folic acid. This spread presents multiple advantages for homeless nutrition : resistance to bacterial contamination, viscosity adapted to people having limited chewing capacity, high energy density, and high nutritional quality/price ratio. Indeed, adding 1 packet of Vitapoche® to a classical food basket increases, for a low cost (21 eurocents/packet), the energy content of the basket, and significantly improves its nutritional quality. This represents an economic advantage for the donor, as well as for the food aid recipient. The acceptability study was conducted in eight sites providing food aid to homeless. During two weeks in each site, the fortified food was systematically proposed (one packet/day) to each individual visiting the site. The evaluation of this new food, named Vitapoche®, showed that homeless would consume the fortified food often or daily, if available. Including fortified street foods in existing food aid programs for homeless is a practical and economic way to help prevent nutritional deficiencies in this population ; Pour mieux prévenir la dénutrition et les déficiences vitaminiques et minérales chez les personnes en situation d'exclusion, nous avons mis au point un aliment enrichi facile à consommer dans la rue : le Vitapoche®. Il s'agit d'une pâte chocolatée résistante à la contamination bactérienne, emballée dans un sachet hermétique. Cette pâte est naturellement riche en potassium et en acides gras oméga-3. Elle a été enrichie en calcium, zinc et vitamines C, ...