title: Grafting versus seed propagated apricot populations: two main gene pools in Tunisia evidenced by SSR markers and model-based Bayesian clustering.
abstract: Apricot was introduced into the Mediterranean Basin from China and Asian mountains through the Middle-East and the Central Europe. Traditionally present in Tunisia, we were interested in accessing the origin of apricot species in the country, and in particular in the number and the location of its introductions. A set of 82 representative apricot accessions including 49 grafted cultivars and 33 seed propagated 'Bargougs' were genotyped using 24 microsatellite loci revealing a total of 135 alleles. The model-based Bayesian clustering analysis using both Structure and InStruct programs as well as the multivariate method revealed five distinct genetic clusters. The genetic differentiation among clusters showed that cluster 1, with only four cultivars, was the most differentiated from the four remaining genetic clusters, which constituted the largest part of the studied germplasm. According to their geographic origin, the five identified groups (north, centre, south, Gafsa oasis and other oases groups) enclosed a similar variation within group, with a low level of differentiation. Overall results highlighted the distinction of two apricot gene pools in Tunisia related to the different mode of propagation of the cultivars: grafted and seed propagated apricot, which enclosed a narrow genetic basis. Our findings support the assumption that grafting and seed propagated apricots shared the same origin.
authors.affiliation: INRA, UR1052 Génétique et Amélioration des Fruits et Légumes, Domaine Saint-Maurice, 84143 Montfavet, France.
authors.forename: Hedia
authors.initials: H
authors.lastname: Bourguiba
authors.forename: Bouchaib
authors.initials: B
authors.lastname: Khadari
authors.forename: Lamia
authors.initials: L
authors.lastname: Krichen
authors.forename: Neila
authors.initials: N
authors.lastname: Trifi-Farah
authors.forename: Sylvain
authors.initials: S
authors.lastname: Santoni
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Audergon
mesh_terms: D000483:Alleles; D001499:Bayes Theorem; D002681:China; D016000:Cluster Analysis; D005060:Europe; D005788:Gene Pool; D040342:Genetic Structures; D014644:Genetic Variation; D018895:Microsatellite Repeats; D008877:Middle East; D058974:Phylogeography; D011110:Polymorphism, Genetic; D027861:Prunus / Q000235:genetics*; D012639:Seeds / Q000235:genetics; D014416:Tunisia