22 research outputs found

    Evaluation of Group Genetic Ancestry of Populations from Philadelphia and Dakar in the Context of Sex-Biased Admixture in the Americas

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    Population history can be reflected in group genetic ancestry, where genomic variation captured by the mitochondrial DNA (mtDNA) and non-recombining portion of the Y chromosome (NRY) can separate female- and male-specific admixture processes. Genetic ancestry may influence genetic association studies due to differences in individual admixture within recently admixed populations like African Americans.We evaluated the genetic ancestry of Senegalese as well as European Americans and African Americans from Philadelphia. Senegalese mtDNA consisted of approximately 12% U haplotypes (U6 and U5b1b haplotypes, common in North Africa) while the NRY haplotypes belonged solely to haplogroup E. In Philadelphia, we observed varying degrees of admixture. While African Americans have 9-10% mtDNAs and approximately 31% NRYs of European origin, these results are not mirrored in the mtDNA/NRY pools of European Americans: they have less than 7% mtDNAs and less than 2% NRYs from non-European sources. Additionally, there is <2% Native American contribution to Philadelphian African American ancestry and the admixture from combined mtDNA/NRY estimates is consistent with the admixture derived from autosomal genetic data. To further dissect these estimates, we have analyzed our samples in the context of different demographic groups in the Americas.We found that sex-biased admixture in African-derived populations is present throughout the Americas, with continual influence of European males, while Native American females contribute mainly to populations of the Caribbean and South America. The high non-European female contribution to the pool of European-derived populations is consistently characteristic of Iberian colonization. These data suggest that genomic data correlate well with historical records of colonization in the Americas

    Molecular variability in Amerindians: widespread but uneven information

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    Tibouchina sellowiana (Cham.) Cogn,: Rooting, anatomy and biochemical analyses in the four seasons

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    The present work tried to verify the effects of application of different concentration of indolebutyric acid (IBA) in talc In solution, in the rooting of cutting of Tibouchina sellowiana (Cham.) Cogn. collected in the four seasons, as well as its anatomical and biochemical variation. The semiharwood cuttings were treated with 0, 1500 and 3000 mg L(-1) indolebutyric acid (IBA), in powder and alchoolic Solutions. After 65 days in a greenhouse, rooting percentage, length and number of roots, cutting with callus percentage and survival, were evaluated. The use of the IBA was efficient in the induction radicial, being indifferent the form in which it was applied. The most promising stations in the formation of the system radicial were the spring (78,75%) with 3000 mg L(-1) or mg kg(-1) IBA and the summer (63,12 %) with 1500 mg L(-1) or mg kg(-1) IBA. (82,50%) with 3000 mg kg(-1) IBA. Considering the cutting in the base of the stakes, in the moment of the cutting, no possible anatomical barrier or structural difference were detected so that it Should promoted variations in the answers of the rooting uring the four seasons. Biochemical analyses done from the cuttings collected in the four seasons revealed that the largest concentrations of total Sugars were obtained in thewinter (83,2 1 mg g(-1)) and in the autumn (72,79 mg g(-1)). The same stations also presented the largest protein concentrations (4,69 and 3,95 mg g(-1) respectively).184167115917

    Propagação vegetativa de espécies silvestres do gênero Piper, com potencial para uso como porta enxertos em pimenta-do-reino (Piper nigrun) Vegetative propagation of wild species of the genus Piper, with potential for use as rootstocks in black pepper (Piper nigrun)

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    O estabelecimento de espécies usadas como porta-enxerto, importantes na olericultura, podem ser multiplicadas por meio da estaquia com auxílio de fitorreguladores. Objetivou-se com este trabalho avaliar a influência do AIB no estabelecimento de espécies nativas do gênero Piper com potencial de uso como porta-enxerto de Piper nigrum. Estacas de P. Arboreum, P. amplum e P. sp foram submetidas a diferentes dosagens de AIB (0, 2000, 4000, 6000 e 8000 mg.L-1) e mantidas em estufa agrícola com irrigação intermitente com temperatura e umidade controlados. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 3x5 (3 espécies de Piper x 5 dosagens de AIB) e composto por 3 repetições por tratamento, sendo cada parcela composta por 10 estacas. A avaliação foi realizada aos 45 dias de transplantio e as variáveis analisadas foram: índice de sobrevivência, número médio de folhas, número médio de brotos e comprimento médio do maior broto. A espécie Piper arboreum apresentou bons resultados referentes ao crescimento da parte aérea independentemente da concentração de AIB empregada.<br>The establishment of species used as rootstock, which are important in horticulture crop scan may be multiplied, with the aid of growth regulators, by cutting. The objective of this study was to evaluate the influence of IBA on the establishment of native species of the genus Piper with potential use as rootstock of Piper nigrum. Cuttings of P. arboreum, P. amplum and P. sp were treated with different concentrations of IBA (0 ,2000, 4000, 6000 and 8000mg.L-1) and maintained in a greenhouse with intermittent irrigation, with the temperature and humidity controlled. The experimental design was completely randomized in a factorial 3x5 plan (3 Piper species x5 doses of IBA) and comprising of three repetitions per treatment, each plot consisting of 10 cuttings. The evaluation was performed at 45 days of transplanting and the analyzed variables were: survival rate, the number of leaves, the number of shoots and the length of the largest shoot. The Piper arboretum species showed the best growth results for the aerial part independent of the IBA concentration used

    Ribeiro's typology, genomes, and Spanish colonialism, as viewed from Gran Canaria and Colombia

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    Four biallelic and six multiallelic Y-chromosome polymorphisms were investigated in 59 Gran Canarian, 60 North African Berber and 46 Spanish subjects. These new data were merged with equivalent literature information to obtain the parental Y-chrosomomal contribution in Gran Canarians, Colombians, and Venezuelans. The results were then compared, for Gran Canarians and Colombians, to those derived from autosomal and mtDNA. In both groups, the Spanish Y-chromosome contribution was much more marked than that estimated using mtDNA. This analysis showed a usual trend in the Spanish Colonial history, characterized by a demographic collapse of the aboriginal population, but with considerable introgression of genes through native women. In accordance to D. Ribeiro's typology for peoples subjected to Colonialism, the Y-chromosomes of these admixed populations are classified as transplanted, their mtDNA as witness, and their autosome sets as new

    Soybean growth and yield after single tillage and species mixture of cover plants

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    The use of cover crops is important for the agricultural crop and soil management in order to improve the system and, consequently, to increase yield. Therefore, the present study analyzed the effect of crop residues of black oat (Avena strigosa Schreb.) (BO) and a cocktail (CO) of BO, forage turnip (Raphanus sativus L.) (FT) and common vetch (Vicia sativa L.) (V) on the emergence speed index (ESI), seedling emergence speed (SES) plant height and soybean yield in different intervals between cover crop desiccation with glyphosate 480 (3 L ha-1) and BRS 232 cultivar sowing. Plots of 5 x 2.5 m with 1 m of border received four treatments with BO cover crops and four with CO as well as a control for each cover crop, at random, with five replications. The plots were desiccated in intervals of 1, 10, 20 and 30 days before soybean seeding. The harvest was manual while yield was adjusted to 13% of moisture content. The experimental design was completely randomized with splitplots and means compared by the Scott and Knott test at 5% of significance. The results showed that CO of cover crops can be recommended for soybean to obtain a more vigorous seedling emergence, from 10 days after cover crop desiccation

    Water intake and digestive metabolism of broilers fed all-vegetable diets containing acidulated soybean soapstock

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    A study was conducted to compare live performance and digestive metabolism of broiler chickens fed all-vegetable diets (All-Veg) compared to a regular diet including animal by-products. Three feeds were formulated and provided to broilers according to the feeding program: pre-starter from 1 to 10 days, starter from 11 to 21 days, and grower from 21 to 35 days. All feeds had corn and soybean meal as major ingredients; however, two of them were all-vegetable diets having either Degummed Soybean Oil (DSO) or Acidulated Soybean Soapstock (ASS) as fat sources. The third diet included poultry by-product and poultry fat. A total number of 360 day-old broiler chicks were allocated to 1m² battery cages, 10 chicks in each, and 12 replicates per treatment. Live performance was similar between groups of birds receiving the different diets with the exception of weight gain, which was increased for birds fed the All-Veg diet with ASS. Birds fed All-Veg diets had increased water intake and produced more excreta with a concurrent reduced feed metabolizability at both ages, regardless of fat source. Metabolizable Energy was not different for the three diets
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