夏蜡梅属的细胞地理学研究

CYTOGEOGRAPHICAL STUDY OF CALYCANTHUS LINNEUS

本文首次报道西美蜡梅(Calycanthus occidentalis)的核型为K(2n)=22=20m(2SAT)+2sm,与美国蜡梅的变种光叶红(C.floridus var.oblongifolius)同属“2A”类型但较为原始,它们都比“1A”的夏蜡梅(C.chinensis)进化,三者由原始到进步的顺序可能为夏蜡梅—→西美蜡梅—→美国蜡梅(光叶红)。夏蜡梅属可能以较原始的夏蜡梅起源于东亚(中国),再东向迁移到北美洲(美国)形成西美蜡梅和美国蜡梅(光叶红)。

The present paper deals with the karyotype analysis of Calycanthus oc-cidentalis Hooker et Arnott. The karyotypic formula is K(2n)=22=2Cm (2SAT) +2sm for the first time, which belongs to '2A' type of Stebbins'[20] as the same as C. flo-ridus var. oblongifolius [3]. These karyotypes are more advanced than that of C. chi-nensis ('lA' [2] ) and sequence of them from primitive to advanced may be C. chinesislllllllllllllll C. occidentalisllllllllllllll C. floridus (var. oblongifolius). The author suggested thatgenera Calyconthus might originate from Eastern Asia (China) by C. chinensis and then form C. occidentalis and C. floridus (var. oblongifolius) after migrating eastward into North America.