Data/hora: 13/06/2024 12:14:28

Provedor de dados: 	74	
País: 	Brazil	
Título: 	Mating system in a natural population of Theobroma grandiflorum (Willd. ex Spreng.) Schum., by microsatellite markers	
Autores: 	Alves,Rafael M.; Artero,Angela S.; Sebbenn,Alexandre M.; Figueira,Antonio.	
Data: 	2003-01-01	
Ano: 	2003	
Palavras-chave: 	Amazonia; Germplasm; Cupuassu; Genetic conservation; Simple sequence repeat.	
Resumo: 	The aim of this research was to study the mating system of a natural population of Theobroma grandiflorum (cupuassu) from Nova Ipixuna, Pará state, using microsatellite markers. Eight polymorphic microsatellite loci were analyzed in eight families, each represented by 10 six-month old seedlings derived from open-pollinated pods. The estimation for the multilocus outcrossing rate (&lt;img border=0 id="_x0000_i1026" src="../../img/revistas/gmb/v26n3/a25img01.gif" align=absmiddle&gt;m = 1.0) and individual outcrossing rate (&lt;img border=0 id="_x0000_i1027" src="../../img/revistas/gmb/v26n3/a25img01.gif" align=absmiddle&gt; = 1.0) for this population suggests that T. grandiflorum may be a perfect outbreeding (allogamous) species. Likewise, for the studied population the estimate for single locus outcrossing rate (&lt;img border=0 id="_x0000_i1028" src="../../img/revistas/gmb/v26n3/a25img01.gif" align=absmiddle&gt;S) was elevated (0.946), but lower than &lt;img border=0 id="_x0000_i1029" src="../../img/revistas/gmb/v26n3/a25img01.gif" align=absmiddle&gt;m, confirming the likely outcrossing character of the species and suggesting the occurrence of 5.4% biparental inbreeding rate (&lt;img border=0 id="_x0000_i1030" src="../../img/revistas/gmb/v26n3/a25img01.gif" align=absmiddle&gt;m - &lt;img border=0 id="_x0000_i1031" src="../../img/revistas/gmb/v26n3/a25img01.gif" align=absmiddle&gt;S). The estimation of genetic divergence (&lt;img border=0 id="_x0000_i1032" src="../../img/revistas/gmb/v26n3/a25img02.gif" align=absmiddle&gt;st) between allelic frequencies in ovules and pollen revealed a deviation from random mating in 75% of the evaluated loci. Likewise, the estimate of correlation of paternity (&lt;img border=0 id="_x0000_i1033" src="../../img/revistas/gmb/v26n3/a25img03.gif" align=absmiddle&gt;P = 0.930) and the mean coefficient of co-ancestrality within families (&lt;img border=0 id="_x0000_i1034" src="../../img/revistas/gmb/v26n3/a25img04.gif" align=absmiddle&gt;XY = 0.501) indicated that the outcrossings were predominantly correlated, and the offspring were full-sibs. These results suggested that for this particular population of T. grandiflorum, the sampling strategy for genetic conservation and breeding should adopt specific models for families derived from correlated outcrossing (full-sibs) and not the ones usually adopted in classic outcrossing species breeding programs (half-sibs).	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300025	
Editor: 	Sociedade Brasileira de Genética	
Relação: 	10.1590/S1415-47572003000300025	
Formato: 	text/html	
Fonte: 	Genetics and Molecular Biology  v.26 n.3 2003	
Fonte: 	info:eu-repo/semantics/openAccess