53 research outputs found

    CIMMYT-selected derived synthetic bread wheats for rainfed environments: Yield evaluation in Mexico and Australia

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    Synthetic backcrossed-derived bread wheats (SBWs) from CIMMYT were grown in the Northwest of Mexico at Centro de Investigaciones Agricolas del Noroeste (CIANO) and sites across Australia during three seasons. During three consecutive years Australia received "shipments" of different SBWs from CIMMYT for evaluation. A different set of lines was evaluated each season, as new materials became available from the CIMMYT crop enhancement program. These consisted of approximately 100 advanced lines (F7) per year. SBWs had been top and backcrossed to CIMMYT cultivars in the first two shipments and to Australian wheat cultivars in the third one. At CIANO, the SBWs were trialled under receding soil moisture conditions. We evaluated both the performance of each line across all environments and the genotype-by-environment interaction using an analysis that fits a multiplicative mixed model, adjusted for spatial field trends. Data were organised in three groups of multienvironment trials (MET) containing germplasm from shipment 1 (METShip1), 2 (METShip2), and 3 (METShip3), respectively. Large components of variance for the genotype x environment interaction were found for each MET analysis, due to the diversity of environments included and the limited replication over years (only in METShip2, lines were tested over 2 years). The average percentage of genetic variance explained by the factor analytic models with two factors was 50.3% for METShip1, 46.7% for METShip2, and 48.7% for METShip3. Yield comparison focused only on lines that were present in all locations within a METShip, or "core" SBWs. A number of core SBWs, crossed to both Australian and CIMMYT backgrounds, outperformed the local benchmark checks at sites from the northem end of the Australian wheat belt, with reduced success at more southern locations. In general, lines that succeeded in the north were different from those in the south. The moderate positive genetic correlation between CIANO and locations in the northern wheat growing region likely reflects similarities in average temperature during flowering, high evaporative demand, and a short flowering interval. We are currently studying attributes of this germplasm that may contribute to adaptation, with the aim of improving the selection process in both Mexico and Australia. (c) 2006 Elsevier B.V All rights reserved

    Molecular diversity; structure and association mapping in a collection of synthetic hexaploid wheat

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    Dissertação de mestrado em Antropologia Médica apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.A presente investigação, ancorada em abordagens teórico-metodológicas utilizadas pela antropologia médica, tem como pendor a análise, através da recolha de narrativas de sujeitos portadores de retinopatia, do sentido atribuído à experiência subjectiva da doença. A retinopatia caracteriza-se por um grupo de doenças degenerativas da retina, que conduzem à perda progressiva da visão ao longo da vida. O sentido da visão está permeado de significados sociais que marcam a vida de quem dele não pode fazer uso. Sendo considerado o sentido mais importante no acesso ao mundo, a experiência das pessoas que o perderam ou o vão perdendo é circunscrita a uma “narrativa de tragédia pessoal” fundada na ideia de incapacidade e infortúnio, erigida pela biomedicina consagrada na modernidade ocidental. Assim, seguindo uma abordagem que concilia a representação e a experiência da doença, o mais intrigante desta dissertação é o tentar perceber como as pessoas com retinopatia experienciam e dão significado à perda da visão ao longo da vida e ao mesmo tempo de que modo a experiência da doença é influenciada pelas representações erigidas sob a perda deste sentido, através da perpetuação de preconceitos e estereótipos. Constata-se que o modo como os indivíduos vivenciam a perda de visão está dependente de concepções, representações e significações de ordem pessoal e social, num quadro sociocultural dinâmico, onde estão em constante reavaliação.The present investigation, anchored in theoretical and methodological approaches used in medical anthropology, has as bias the analysis, through the collection of narratives of patients with retinopathy, of the meaning assigned to the subjective experience of disease. The retinopathy is characterized by a group of degenerative diseases leading to the progressive loss of sight over the life. The sense of sight is permeated with social meanings which mark the life of who cannot make use of it. Being considered the most important sense in the access to the world, the experience of people who have lost it or are losing it is circumscribed to a “narrative of personal tragedy” founded in idea of disability and misfortune, erected by the biomedicine consecrated in Western modernity. Thus, following an approach that reconciles the representation and the experience of disease, the most intriguing of this dissertation is to try to understand how people with retinopathy experience and give meaning to the loss of sight over the life and, at the same time, in what way the experience of disease is influenced by the representations erected under the loss of this sense, through the perpetuation of prejudice and stereotypes. It is noted that the way in which individuals live the loss of sight is dependent of conceptions, representations and meanings of personal and social order, in a dynamic sociocultural frame, were they are in constant reevaluation
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