22 research outputs found

    Anatomical aspects of the embryo and initial development of Oenocarpus minor Mart: a palm tree from the Amazon

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    The anatomy of the embryo and the initial germination phase of O. minor seeds are examined here. Ripe fruits were collected from five individuals, the pulp removed, and the seeds sown in beds with sandy substrate in a greenhouse with 50% shade. Germination follow-up was made by collecting different stages of development. The anatomical study done according to usual techniques of light microscopy. The embryo is capitate and occupies a central position in the basal region of the seed. The embryogenic axis is located in the proximal region in a position that is oblique to the cotyledon axis. The cotyledon is formed by parenchymatous, procambial and protodermic tissue. The vascular bundles lie along the peripheral zone of the distal region to the embryogenicaxis. After 14 days, the primary rootemerges; after 21 days, the first cotyledon sheath and after 35 days, the second cotyledon sheath, and the seedling emerges above the substrate. Germination is of the ligule adjacent type.Neste trabalho foi feita a anatomia do embrião e a fase inicial da germinação da semente de O. minor. Frutos maduros de cinco indivíduos foram despolpados e as sementes obtidas foram semeadas em canteiros contendo substrato areia em casa de vegetação com sombreamento a 50%. O acompanhamento da germinação foi feito através de coletas das diferentes fases do desenvolvimento. O estudo anatômico foi realizado conforme técnicas usuais de microscopia de luz. O embrião é capitado. O eixo embrionário localiza-se na região proximal em posição oblíqua ao eixo cotiledonar. O cotilédone é formado por tecido parenquimático, procambial e protodérmico. Os feixes vasculares ocorrem ao longo da zona periférica da região distal até ao eixo embrionário. Aos 14 dias é emitida a raiz primária. Aos 21 dias forma-se a primeira bainha cotiledonar e aos 35 dias a segunda bainha cotiledonar ocorrendo à emergência da plântula acima do substrato. A germinação é do tipo adjacente ligular

    Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

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    A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16%) and PGD*A (2%), respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39%) of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level). Of the latter, the two most interesting (since they were also observed in other studies) were MNSs/Duffy and Rh/ACP
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