Annals of Botany 89: 559-562, 2002
© 2002 Annals of Botany Company
Seed Germination and Reproductive Features of Lysimachia minoricensis (Primulaceae), a Wild-extinct Plant
1Jardín Botánico de Valencia, Universidad de Valencia c/Quart 80, E-46008, Valencia, Spain and 2Centre de Recerca Ecològica i Aplicacions Forestals (CREAF), Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Spain
* For correspondence. Fax: +34 963156826, e-mail rossello{at}uv.es
Received: 25 May 2001 Returned for revision: 2 September 2001; Accepted: 3 December 2001 .
Lysimachia minoricensis is one of the few Mediterranean endemic plants (Minorca, Balearic islands) that has gone extinct in the wild but which persists as extant germplasm or cultivated plants in several botanical gardens. Reproductive features (seed set, number of seeds per capsule, seed weight) and germination responses to constant temperatures, sea water and dry-heat pre-treatments were investigated to determine the extent to which they may have influenced the extinction of the species. Seed set in Lysimachia is not dependent on pollinators, suggesting a functional selfer breeding system. Most plants produced a large mean number of fruits (23·2) and seeds (46·6), and the mean production of seeds per individual was estimated to be almost 1100. Overall, no highly specific requirements were observed for seed germination. Seed germination was not inhibited in the dark, and a high germinability (over 87 % in all cases) was recorded in most experiments, with the exception of those performed at low temperatures (5 and 10 °C). These data suggest that fertility and seed viability were not the major causes of extinction. The high reproductive performance of L. minoricensis is in striking contrast to its status as a wild-extinct plant, suggesting that extrinsic factors were responsible for its extinction.
Key words: Seed germination, Mediterranean flora, extinct taxa.