6533b7d5fe1ef96bd1264fdc

RESEARCH PRODUCT

RAPD differentiation between Borderea pyrenaica and B. chouardii (Dioscoreaceae), two relict endangered taxa

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As currently circumscribed, the genus Borderea Mieg. comprises two narrowly distributed European taxa, Borderea pyrenaica (Bub.) Mieg. and B. chouardii (Gaussen) Heslot. An accumulation of facts such as that both species share a very close overall morphology, that only a single population of Borderea chouardii is known, and that they live in contrasting environments has led some authors to suggest that B. chouardii is a mere ecotype of the more widespread B. pyrenaica. We tested this hypothesis using RAPD markers in four populations of Borderea, three of them identified as B. pyrenaica and the other one representing the only known population of B. chouardii. Eleven out of twenty assayed primers yielded consistent and reproducible polymorphims between accessions. Overall, 145 reproducible bands were scored, 116 of which (80.0%) were variable between samples. Mean similarity values within Borderea pyrenaica populations were lower (0.78) than those obtained for B. chouardii (0.94); pairwise similarities amon...