日本産キク属の種 : 細胞学および細胞遺伝学からみたその実体  [in Japanese] Species of wild chrysanthemums in Japan : Cytological and Cytogenetical view on its entity  [in Japanese]

1. Cytological and cytogenetical characteristics of the genus Chrysanthemum in Japan were summarized. 2. From the cytological viewpoint, some taxonomical and phytogeographical problems were raised here, that is: (1) In Kyushu diploid species with white-ray flowers which is considered as Ch. makinoi could not be found. At lease at present, Kyushu should be excluded from the geographical distribution of Ch. makinoi. (2) There are two polyploids, tetraploid with 2n=36 and hexaploid with 2n=54, in the Ch. indicum group. The hexaploids have been mainly found in the northern part of Kyushu and the eastern part of Chugoku district. This distributional pattern differs from that of Ch. aphrodite which is known as a hexaploid and similar to Ch. indicum. Interrelationships between these two species and taxonomical revision on this complicated Ch. indicum group need further investigations. (3) Ch. weyrichii was considered as a member of Ch. zawadskii by KITAMURA (1981) and described its chromosome number as 2n=54. However the present authors have counted 2n=72 chromosomes in the materials from Oshoro, Hokkaido (unpublished). So far as those found in Japan is concerned cytologically, Ch. weyrichii differs from Ch. zawadskii. 3. From the viewpoint of their crossabilities, the genus Chrysanthemum in the sense of KITAMURA (1940) is considered to be the most acceptable treatment of the grouping. The subdivided system by KITAMURA (1978, 1981) can also be accepted because hybrid sterilities and differences in karyotypes exist between some species in the genus. 4. some questions in the list of chromosome numbers on Chrysanthemum compiled by FEDOROV (1974) were pointed out as follows: (1) 2n=19 for Ch. rupestre as a report by KITAGWA & NAGAMI (1960) might be 2n=18. (2) 2n=54 for Ch. zawadskii as a report by SHIGENAGA (KITAMURA 1957) should be n=9 for Ch. z. var. latilobum. (3) The species name Ch. sibilicum which was reported as 2n=54 by SHIMIZU (1958a) should be Ch. zawadskii var. latilobum. (4) 2n=18 for Ch. hakusanense reported by ISHIKAWA (1916) should be n=27. (5) 2n=54 for Ch. ornalum as a report by DOWRICK (1953) might be 2n=72.