Using AFLP Markers for the Analysis of the Genetic Diversity of Apricot Cultivars in Tunisia
Apricot (Prunus armeniaca L.) culture is present in a wide range of areas and microclimates in Tunisia. Each of them contains several specific cultivars and shows a high level of morphological diversity. To characterize the related diversity, surveys were performed in the four main apricot cultivation areas, where 31 cultivars representing apricot landraces were sampled. DNA was extracted and amplified with five different EcoRI–MseI AFLP primer combinations. Autoradiographs revealed 203 polymorphic markers in a total of 295 detected fragments. A set of redundant marker patterns was identified and deleted from the binary data matrix, data analysis being performed on a total of 167 polymorphic markers. In a dendrogram calculated by the Ward clustering technique, two major groups were identified, separating nine cultivars from the other 22. Three subgroups have been revealed in each of the main groups. The groups and subgroups identified on the genetic basis are closely related to the geographic origin of the cultivars. Analysis of the actual repartition suggested at least the introduction of two independent gene funds in the northern and central prospected areas, followed by a local diversification and then a dissemination phase. Their interaction occurred at least in the two sites of Testour and Sbikha.