Afro-Derived Amazonian Populations: Inferring Continental Ancestry and Population Substructure

A panel of Ancestry Informative Markers (AIMs) was used to identify population substructure and estimate individual and overall interethnic admixture in 294 individuals from seven African-derived communities of the Brazilian Amazon. A panel of 48 biallelic markers, representing the insertion (IN) or the deletion (DEL) of small DNA fragments, was employed for this purpose. Overall interethnic admixture estimates showed high miscegenation with other ethnic groups in all populations (between 46% and 64%). The proportion of ancestral genes varied significantly among individuals of the sample: the contribution of African genes varied between 12% and 75%; of European genes between 10% and 73%; and of Amerindians genes between 8% and 66%. The obtained data reveal a high contribution of Amerindian genes in these communities, unlike in other African-derived communities of the Northeast and the South of Brazil. In addition, the majority of the Amerindian contribution may result from the preferential inclusion of indigenous women in the African descent groups. High heterogeneity of the proportion of interethnic admixture among analyzed individuals was found when the proportion of ancestral genes of each individual of the sample was estimated. This heterogeneity is reflected in the fact that four populations can be considered as substructured and that the global African descent sample is possibly formed by two subpopulations

Allelic database and accession divergence of a Brazilian mango collection based on microsatellite markers.

Allelic patterns and genetic distances were examined in a collection of 103 foreign and Brazilian mango (Mangifera indica) accessions in order to develop a reference database to support cultivar protection and breeding programs. An UPGMA dendrogram was generated using Jaccard coefficients from a distance matrix based on 50 alleles of 12 microsatellite loci. The base pair number was estimated by the method of inverse mobility. The cophenetic correlation was 0.8. The accessions had a coefficient of similarity of from 30 to 100%, which reflects high genetic variability. Three groups were observed in the UPGMA dendrogram; the first group was formed predominantly by foreign accessions, the second group was formed by Brazilian accessions, and the Dashehari accession was isolated from the others. The 50 microsatellite alleles did not separate all 103 accessions, indicating that there are duplicates in this mango collection. These 12 microsatellites need to be validated in order to establish a reliable set to identify mango cultivars

Enraizamento ex vitro da cultivar de mamona BRS nordestina a partir de brotos micropropagados in vitro.

bitstream/CNPA/19672/1/COMTEC250.pd

Efeito do tiadiazuron na micropropagação in vitro de dois genótipos de mamona via organogênese.

Made available in DSpace on 2011-07-08T01:02:43Z (GMT). No. of bitstreams: 1 v14n04a04.pdf: 165472 bytes, checksum: 0047e6041416c36dce88495e7b726d38 (MD5) Previous issue date: 2010-04-13201

Competicao entre cultivares de tomate (Lycopersicum esculentum Mill) em seis epocas de semeadura, no Piaui: II - Resultados obtidos na primeira e segunda epoca.

bitstream/item/96911/1/PAND200001.pd

Qualidadee longevidade de hastes de Alpinia purpurata 'Red Ginger' mantidas sob diferentes pHs.

Este trabalho objetivou identificar possíveis alterações físicas e físico-químicas após tratamento com solução de fortificação com sacarose em brácteas e região periférica e externa do caule de hastes florais de Alpínia vermelha (Alpinia purpurata)