ISSR Variation in Olive-tree Cultivars from Morocco and other Western Countries of the Mediterranean Basin

Abstract

In olive tree (Olea europaea L.), 12 varieties (or cultivars) representing the main domesticated material used in Morocco and 19 olive cultivars used extensively in five countries of the western Mediterranean Basin, were analysed using inter-simple sequences repeat (ISSR) markers which had never been used previously for extensive discrimination of cultivars. Four selected primers produced a total of 26 polymorphic reproducible amplification fragments. Combinations of these ISSR markers allowed to identify 25 of the 31 cultivars. Two additional combinations were distinguished, each corresponding to three Moroccan cultivars or local varieties. Evidence of a multiclonal composition in the widely cultivated variety 'Picholine marocaine' was obtained by the identification of three genotypes within the four morphologically distinct clones analysed in the variety. In the UPGMA phenogram based on the proportion of shared ISSR fragments, five groups of cultivars were distinguished at the 40% critical value of similarity. Four of the groups contained varieties from various geographic origins, as the consequence of successive human migrations which favoured olive dispersion throughout the Mediterranean Basin. However, the fifth group gathered together 9 of the 12 Moroccan cultivars and very few cultivated clones from Greece and Spain. The results suggest that most of the Moroccan cultivars are closely related and likely originated from local domestication.

Intra-specific genetic diversity in wild olives (Olea europaea ssp cuspidata) in Hormozgan Province, Iran

“…The high level of polymorphism at ISSR loci also indicates high genetic variability in wild olive trees, which is in agreement with other studies made on cultivated (Gemas et al, 2004;Terzopoulos et al, 2005;Essadki et al, 2006;Gomes et al, 2009;Martins-Lopes et al, 2009) and wild olive trees (Hess et al, 2000).…”

Molecular identification of Greek olive(Olea europaea) cultivars based on microsatellite loci

“…Most of the genetic diversity was found to be attributable to differences among genotypes within a country. Belaj et al (2002), Terzopoulos et al (2005) and Essadki et al (2006) observed various groupings of Greek cultivars based on ISSR markers. Omrani-Sabbaghi et al (2007) did not find any particular clustering between seven Greek genotypes using SSR markers.…”

“…Several molecular studies have discriminated various Greek olive cultivars (Fabbri et al, 1995;Besnard et al, 2000Besnard et al, , 2001aBelaj et al, 2001Belaj et al, , 2002Nikoloudakis et al, 2003;Rallo et al, 2003;Owen et al, 2005;Terzopoulos et al, 2005;Hagidimitriou et al, 2005;Montemurro et al, 2005;Díaz et al 2006b;Essadki et al, 2006;Omrani-Sabbaghi et al, 2007;Bracci et al, 2009). Greek genotypes seem to carry the same chloroplast DNA polymorphisms (Besnard et al, 2000) and the same mitotypes (ME1), except Amigdalolia, which carries the ME2 mitotype (Besnard et al, 2001b).…”

Genetic relationship among wild, landraces and cultivars of hazelnut (Corylus avellana) from Portugal revealed through ISSR and AFLP markers

“…In other woody species, AFLP and ISSR have also been used in analysis of genetic diversity in Citrus spp. (Fang and Roose 1997;Biswas et al 2011), Vitis vinifera L. (Moreno et al 1998;Ergül et al 2006) or Olea europea L. (Essadki et al 2006;Albertini et al 2011). In Portugal, the number of landraces has decreased in the last decades and the few ones actually identified have been poorly characterized.…”