Karyotypes on Five Species of Japanese Geum (Rosaceae)

Abstract

Karyotypic studies were done on five Japanese species of Geum. These Geum species had gradual and symmetric karyotypes in common. Karyotypic formulae of the five species were the following: G. aleppicum (6x), 2n=42=24m+10sm+4^tsm+4st; G. calthaefolium var. nipponicum (6x), 2n=42=32m+6sm+2st+2^tst; G. japonicum (6x), 2n=42=26m+8sm+4^tsm+4st; G. macrophyllum var. sachalinense (6x), 2n=42=26m+8sm+4^tsm+4st; G. pentapetalum (2x), 2n=14=8m+4sm+2^tt. The study of karyotypes of the Japanese Geum species reveals that G. aleppicum, G. japonicum and G. macrophyllum var. sachalinense have close relationship, whereas G. calithaefolium var. nipponicum is distinct from the other hexaploid Geum. Also, G. pentapetalum was quite distinct from the other Japanese Geum species studied.