title: Genetic Relationships among Tall Coconut Palm (Cocos nucifera L.) Accessions of the International Coconut Genebank for Latin America and the Caribbean (ICG-LAC), Evaluated Using Microsatellite Markers (SSRs).
abstract: The diversity and genetic relationships among two accessions of tall coconut palms collected in Brazil and seven accessions introduced from different geographic regions of the world were analyzed using 25 microsatellite primers, 19 of which were polymorphic and detected between 4 and 10 alleles per locus, with an average of 6.57. The observed and expected heterozygosity ranged from 0.25 and 0.40 in the Rennell Islands Tall (RIT) accession to 0.54 and 0.62 in the Polynesian Tall (PYT) accession. The analysis of genetic structure resulted in the formation of five distinct groups. The first group was formed by the accessions Brazilian Tall-Praia do Forte (BRTPF), Brazilian Tall-Merepe (BRTMe) and West African Tall (WAT); the second group consisted of Malaysian Tall (MLT); the third group of RIT; the fourth group of Vanuatu Tall (VTT); and the fifth group of Rotuman Tall (RTMT), Tonga Tall (TONT) and PYT. The dendrogram based on the nearest-neighbor method detected the formation of two main groups and five subgroups, indicating that the genetic relationships of the accessions are based on their geographic regions of origin. The analyses revealed genetic relationships between the accessions collected in Brazil and the accession from Africa, and among palms from South East Asia and the South Pacific, confirming the common origin of these accessions. The information obtained in this study can guide decisions on germplasm conservation activities and the efficient selection of genetically divergent parents for use in coconut breeding programs in Brazil, which are attempting to select for disease resistance, mainly to lethal yellowing, among other characteristics.
authors.affiliation: Federal Rural University of Semi-Árido/Embrapa Coastal Tablelands, Aracaju, Sergipe, Brazil.
authors.forename: Carina Mendes
authors.initials: CM
authors.lastname: Loiola
authors.affiliation: North Fluminense State University (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Alinne Oliveira Nunes
authors.initials: AO
authors.lastname: Azevedo
authors.affiliation: Embrapa Coastal Tablelands, Aracaju, Sergipe, Brazil.
authors.forename: Leandro E C
authors.initials: LE
authors.lastname: Diniz
authors.affiliation: Embrapa Coastal Tablelands, Aracaju, Sergipe, Brazil.
authors.forename: Wilson Menezes
authors.initials: WM
authors.lastname: Aragão
authors.affiliation: North Fluminense State University (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Carlos Diego de O
authors.initials: CD
authors.lastname: Azevedo
authors.affiliation: North Fluminense State University (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Pedro Henrique A D
authors.initials: PH
authors.lastname: Santos
authors.affiliation: North Fluminense State University (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Helaine Christine C
authors.initials: HC
authors.lastname: Ramos
authors.affiliation: North Fluminense State University (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Messias Gonzaga
authors.initials: MG
authors.lastname: Pereira
authors.affiliation: Embrapa Coastal Tablelands, Aracaju, Sergipe, Brazil.
authors.forename: Semíramis R Ramalho
authors.initials: SR
authors.lastname: Ramos
mesh_terms: D017691:Caribbean Region; D003059:Cocos / Q000235:genetics*; D030561:Databases, Nucleic Acid; D056426:Genetic Loci; D014644:Genetic Variation; D005843:Geography; D007843:Latin America; D018895:Microsatellite Repeats / Q000235:genetics*; D010802:Phylogeny