|Budget Amount *help
¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 2004 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 2003 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 2002 : ¥1,900,000 (Direct Cost : ¥1,900,000)
Chromosome numbers of the family Asclepiadaceae from Japan including the Ryukyus were reported. Morphological and molecular phylogenetic studies showed Cynanchum matsumurae(Asclepiadaceae), an endemic species of the central Ryukyus, belongs to the genus Tylophora.
Cytological and molecular phylogenetic studies showed Ixeris nakazonei (Asteraceae), an endemic species of the Ryukyus, derived from polytopic interspecific hybrids between Ixeris repens and I.debilis. Ixeris nakazonei was morphologically and cytologically variable, and the higher polyploid cytotypes of I.nakazonei tend to be distributed in the more southerly area in the Ryukyus.
Chromosome numbers of the genera Psychotria and Ophiorrhiza (Rubiaceae) from the Ryukyus were reported. Molecular phylogenetic analysis of the genus Ophiorrhiza of the Ryukyus showed O.japonica var.amamiana, an endemic to the central Ryukyus, is a relict and distinct taxon.
Molecular phylogenetic studies on the Eurya(Theaceae) of the Ryukyus showed E.zigzag, an endemic to the central Ryukyus, is a relict species and is distinct from E.yaeyamensis, an endemic to the southern Ryukyus, while E.emariginata var. minutissima is a neoendemic species differentiated from E emarginata var. emarginata on the cloud forests of the central Ryukyus.
Morphological comparison of Selaginella biformis, and closely related S.utchinensis and S.davidii (Selaginellaceae) from Okinawa Island, the central Ryukyus, was carried out. The present observation showed the plants reported as S.davidii is S.utchinensis, and the difference of S.biformis and S.utchinensis is not cleaer.