EFFECT OF THE BREEDING SYSTEM ON THE GENETIC-STRUCTURE IN 3 CEPHALANTHERA SPP (ORCHIDACEAE)

The genetic variation of seven enzymes for a total of nine loci was investigated in three species of terrestrial orchids of the genus Cephalanthera: C. longifolia, C. rubra, and C. damasonium. These species are characterized by presenting different breeding types: outbreeding, outbreeding with facultative vegetative reproduction, and inbreeding, respectively. Electrophoretic evidence points to a difference in the behaviour of each of the three species which seems strictly related to the breeding type. On the basis of our results C. longifolia behaves as a normal outbreeder, while C. rubra presents the influence of vegetative reproduction in some populations and not in others. C. damasonium shows a total lack of both among and within populations genetic variation, which is most probably due to the autogamic breeding type.