Proceedings of the XLVII Italian Society of Agricultural Genetics - SIGA Annual Congress

Verona, Italy - 24/27 September, 2003

ISBN 88-900622-4-X

Poster Abstract - 5.45

GENOMIC CHARACTERIZATION OF OLEA EUROPAEA VARIETIES BY 26S RFLP BASED POLYMORPHYSM AND FISH TECHNOLOGIES

L. BRUNO*, T. PANGARO*, R. COZZA*, D. GIANNINO**, M.B. BITONTI*

*) Università degli Studi della Calabria-Dip.to di Ecologia, Ponte P. Bucci, cubo 6B, 87030 Arcavacata di Rende (Cosenza)

**) Istituto di Biologia e Biotecnologia Agraria (sez.di Roma), Via Salaria km 29300, 00016 Monterotondo Scalo (Roma)

Olea europea, RFLP, FISH

Olive (Olea europaea L.) is one of the most characteristic species of the Mediterranean area and one of the oldest agricultural tree crops. Breeding of olive-trees has been limited due to the long juvenile phase and the lack of the phylogenetic relationships among Olea species. Within the Olea species, two sub-species are distinguished: sativa and sylvestris. The former includes the cultivated varieties which are self-incompatible and thus vegetatively propagated; the latter harbours varieties which only reproduce by sexual means. Olive feral forms derive from crosses between varieties belonging to sativa and sylvestys subspecies. Molecular markers of polymorphism have turned to be powerful tools to improve classification of Olea groups, define phylogenetic relations among cultivars, distinguish close related varieties and screen for genotypes in genetic breeding programme. In the present study, RFLP markers and FISH techniques were used to analyse a set of Olea europea cultivars representative of Calabria and ancestral forms from Sardinia. An rDNA 26S derived fragment of Olea europaea was used to probe genomic DNA restricted with different enzymes and distinctive polymorphism was revealed between Calabrian cultivars and the Sardinian wild forms. Inter-cultivar polymorphism is currently being analysed and cluster types will be possibly presented. Southern analyses with rare cutting enzymes suggests that rDNA cistrons are organized in at least four main polymorphic clusters in both Calabrian cultivars and Sardinian forms. Moreover, FISH performed on Calabrian cultivars displayed at least four clear signals near the nucleolus region in the interphasic nuclei.