XVI International Botanical Congess

Pteris is a genus of around 250 species of tropical and subtropical distribution, with only a few species growing in temperate regions, one of them is Pteris incompleta, native to the Macaronesian and Mediterranean Regions. Details of its reproductive biology in laboratory conditions are given in this study. Gametophyte development follows the Ceratopteris type. Archegoniate prothallia are produced first or at the same time than antheridiate, a small proportion of both becoming bisexual. Female gametophytes of P. incompleta are able to induce a) precocious formation of antheridia in young prothallia of P. incompleta and P. vittata, and b) germination of spores and formation of antheridia in dark conditions in P. vittata. This suggests the existence of an antheridiogen system in P. incompleta similar to the one reported for P. vittata.