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

Giardini Naxos, Italy - 18/21 September, 2002

ISBN 88-900622-3-1

Poster Abstract - 3.13

SPECIES RELATIONSHIPS IN ECHINACEA INFERRED FROM AFLP FINGERPRINTS AND IN SITU HYBRIDIZATION

FALISTOCCO E., MORETTI C., RUSSI L.

Dipartimento di Biologia Vegetale e Biotecnologie Agroambientali, Borgo XX Giugno 74, 06121 Perugia Italy

Echinacea, AFLP, phylogenesis, genomic in situ hybridization, ribosomal DNA

The genus Echinacea (Compositae) is native to the prairies of North America from which it spread towards South regions down to Texas and Georgia. The genus comprises about twenty species, with E.angustifolia D. C. (2n=22), E. purpurea (L.) Moench (2n=22) and E. pallida Nutt. (2n=44) being the most common. E angustifolia was widely used by indigenous popolations of North America for cicatrizing hurts and to treat snakebites. These species are receiving an increased interest in pharmacology due to their immunological properties. The research in this field is very active but genetics studies are scarce.

The objective of this work is the genetic characterization of E.angustifolia,E. purpurea and E. pallida by means of AFLP markers and to look at their phylogenetic relationships.

The molecular analysis was based on ten primer combinations.The scoring of AFLP gels showed the presence of 991 markers. Of these, 429 were monomorphic (43%), while 562 were polymorphic (57%). Of the latter group, as many as 275 fragments were discriminant, that is, unique to all plants of a particular species. The analysis showed that as many as 89 fragments were unique to to E. purpurea, 29 to E. angustifolia and 26 to E. pallida. In addition the three species could also be distinguished by employing combinations of fragments. The study showed also the most powerful combination of primers for species discrimination.

The cluster analysis showed high similarity between E. angustifolia and E. pallida, with E. purpurea clustering apart This suggests that E. pallida could origin from E. angustifolia by polyploidization, but GISH analysis is not revealing any signals of cross hybridization. Attempts to map ribosomal gene sites have also been made. GISH studies are giving insights of genomic structure of the three species.