Karyotypic relationships amongAstilboides,Bergenia,Darmera, andMukdeniaand their implications for subtribal boundaries in Saxifrageae (Saxifragaceae)

摘要

Chromosomal studies have revealed that 2nensp;=ensp;34 inAstilboides,Darmera,Mukdenia, andBergeniaand that these genera have very similar karyotypes. Few taxa of Saxifrageae havexensp;=ensp;17, and chromosomal data therefore suggest that these four genera form a natural group. The generic affinities suggested by chromosomal data are not in agreement with the traditional interpretation of relationships in Saxifrageae.Astilboideshas been placed in subtribe Astilbinae, whileBergenia,Darmera, andMukdeniawere considered members of Saxifraginae. The data presented here, in conjunction with data from earlier chromosomal studies, indicate that traditional subtribal boundaries do not accurately reflect relationships in tribe Saxifrageae.