Caractérisation Agronomique Et Moléculaire Des Cultivars D´abricotier (prunus Armeniaca L.), Dans Les Régions Du Hodna Et De L´aurés, Algérie: Diversité, Structure De La Population Et Association Génétique

Résumé: Knowledge and characterization of phyto-genetic resources are major issues in order to protect and enhance our genetic heritage. Good conservation and management of local genetic resources requires prior assessment and identification of the variability present in in situ and ex situ collections. The apricot tree (Prunus amreniaca L.) is a species characterized by a very rich diversity, mainly located around the Mediterranean basin. The study carried out consists of a contribution to the evaluation of the genetic diversity of the apricot tree (Prunus amreniaca L.) In Algeria which contains a large and little known range and this through the characterization for the first time of 84 apricot accessions. Represented by 22 spontaneous accessions and 62 accessions resulting from grafting which are distributed at the level of the areas of Hodna and Aurès which represent the oldest and most productive areas of apricot. In total, thirty-seven phenotypics markers (16 quantitatives 21 qualitatives), relating to the phenologicals, pomologicals and morphologicals characteristics of the tree, described in the UPOV descriptors (2007), and ten microsatellites markers were used to analyze it, of existing genetic diversity. In parallel, another study was carried out to evaluate the self (in) -compatibility of the 84 accessions of the Hodna and Aurès areas by the identification of the S allele by PCR analysis using specific primers. For the identification and differentiation of self-compatibility (Sc) and self-incompatibility (S8) alleles. Exploitation of the results of the statisticals analysis of quantitatives and qualitatives phenotypics data from this study showed highly significant phenotypics differences between the accessions studied. Indeed, the phenotypics characters used, for the organs of the vegetative and reproductive part, indicated a fairly significant genetic variability between the 84 accessions studied, with a relatively high degree of polymorphism. This variation at the phenotypic level is most likely due, in large part, to variation in the genetic components of differents cultivars. A second approach, based on molecular tools, made it possible to resolve the cases of disambiguation and synonymy within the different accessions studied where it turned out that the spontaneous accessions are all genetically differents with 22 totally differents accessions. The same was observed for accessions resulting from grafting where 36 cases of disambiguations were identified and one case of synonymy and two cases of mutations were found in cultivars Bulida and Bedai. The results of pollen compatibility analyzes indicate that apricot cultivars represent an interesting source of new self-compatible genetic material where 77.42% of accessions resulting from grafting are self-compatibles against 46% for spontaneous accessions with a capacity of adaptation to drought conditions, an interesting characteristic for Mediterranean apricot breeding programs

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