Titre : | High level of genetic differentiation for allelic richness among populations of the argan tree [Argania spinosa (L.) Skeels] endemic to Morocco. | Type de document : | texte imprimé | Auteurs : | A. El mousadik, Auteur ; R. J. Petit, Auteur | Editeur : | Heidelberg : Springer | Année de publication : | 1996 | Importance : | pp. 832-839 | Présentation : | ill., graph., tabl., réf. | Note générale : | Extrait de Theoretical and applied genetics - Vol.92 - n°7 | Langues : | Anglais (eng) | Résumé : | Genetic diversity at nine isozyme loci was surveyed in an endangered tree species, the argan tree, endemic to south-western Morocco. The species is highly diverse (3.6 alleles/locus) with populations strongly differentiated from each other (FST=0.25). This example is used to illustrate a method for standardizing measures of allelic richness in samples of unequal sample sizes, which was developed for the estimation of the number of species and relies on the technique of rarefaction. In addition, it is shown that the measure of subdivision, ρST, obtained when allelic richness is used in place of h (Nei's index of diversity), is much larger than the FST [e.g. ρST(40)=0.52, where (40) indicates the specified sample used to estimate the allelic richness]. This suggests that rare alleles (which strongly influence measures of allelic richness) have a more scattered distribution than more frequent ones, a result which raises special conservation issues for the argan tree. | Type de document : | Tiré à part | Permalien de la notice : | https://infodoc.agroparistech.fr/index.php?lvl=notice_display&id=182077 |
High level of genetic differentiation for allelic richness among populations of the argan tree [Argania spinosa (L.) Skeels] endemic to Morocco. [texte imprimé] / A. El mousadik, Auteur ; R. J. Petit, Auteur . - Heidelberg : Springer, 1996 . - pp. 832-839 : ill., graph., tabl., réf. Extrait de Theoretical and applied genetics - Vol.92 - n°7 Langues : Anglais ( eng) Résumé : | Genetic diversity at nine isozyme loci was surveyed in an endangered tree species, the argan tree, endemic to south-western Morocco. The species is highly diverse (3.6 alleles/locus) with populations strongly differentiated from each other (FST=0.25). This example is used to illustrate a method for standardizing measures of allelic richness in samples of unequal sample sizes, which was developed for the estimation of the number of species and relies on the technique of rarefaction. In addition, it is shown that the measure of subdivision, ρST, obtained when allelic richness is used in place of h (Nei's index of diversity), is much larger than the FST [e.g. ρST(40)=0.52, where (40) indicates the specified sample used to estimate the allelic richness]. This suggests that rare alleles (which strongly influence measures of allelic richness) have a more scattered distribution than more frequent ones, a result which raises special conservation issues for the argan tree. | Type de document : | Tiré à part | Permalien de la notice : | https://infodoc.agroparistech.fr/index.php?lvl=notice_display&id=182077 |
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