Caractérisation moléculaire et relation génétique entre les morphotypes les plus connus d’une espèce marocaine rare et menacée, Argania spinosa (Sapotaceae) à l’aide de marqueurs RAPD et SSR

Abstract

• The objective of this work is the molecular characterization of most common identified morphotypes of critically endangered rare Moroccan species Argania spinosa. • Eighteen RAPD markers and twenty SSR markers have been assayed in 38 argan tree accessions from the three most commonly identified morphotypes: oval, spherical and spindle fruit types. • A total of 140 polymorphic RAPD bands were detected out of 146 bands. The number of presumed alleles revealed by the SSR analysis ranged from 1 to 5 alleles per locus with a total number of 32 alleles identified. Results demonstrated an extensive genetic variability within the tested argan accessions. RAPDs presented a high level of polymorphism and greater information content than SSRs. • Our results could indicate that Vitellaria paradoxa is genetically closer to argan than Manilkara huberi. In addition, the correlation between the clustering based on RAPD and SSR markers were in general low. The observed clustering could be better explained according to geographic proximity than morphotype. For this reason the traditional morphological characterization of the argan accessions in morphotypes (according to fruit phenotype) seem not to be in correlation to the real genetic background (genotype) of this specie. The implications of these results in the creation of effective germplasm core collection in argan have been also discussed.