东亚植物区系中若干双子叶植物的染色体新计数及其系统学和进化意义  

NEW CHROMOSOME COUNTS OF SOME DICOTS IN THE SINO-JAPANESE REGION AND THEIR SYSTE-MATICS AND EVOLUTIONARY SIGNIFICANCE

作　　者：徐炳声[1] 翁若芬 栗田子郎 

机构地区：[1]中国科学院植物研究所系统与进化植物学开放研究实验室,北京100093 [2]上海自然博物馆植物学分馆,上海200232 [3]千叶大学理学部系统发育植物学实验室

出　　处：《植物分类学报》1994年第5期411-418,共8页Acta Phytotaxonomica Sinica

摘　　要：本文报道了东亚植物区系中双子叶植物9个种的体细胞染色体新计数,其中6个是属的新计数,并对这些资料与有关的科或属在系统学和进化上的意义作了讨论。New somatic chromosome numbers for nine species eight families and eight genera in the Sino-Japanese Region are reported here as shown in Table 1. Data of six genera are previously unknown cytologically. The bearings of these new data on the systematics and evolution of the related species, genera or families are discussed as follows; (1) Platy-carya strobilacea Sieb. et Zucc. (Juglandaceae). The chromosome number of this species is 2n = 24, with a basic number of x = 12, which deviates from 2n=32 occurred in Juglans, Carya, Pterocarya and Engelhardtia with the basic number x=16. The Juglandaceae appears to be fundamentally paleotetraploid, with an original basic number of x = 6 in Platy- carya and x = 8 in the other four genera, although secondary polyploidy occurs in Carya. Based on the remarkable morphological differences between Platycarya and the rest seven genera of the family, Manning (1978) established two subfamilies; Platycaryoideae for Platycarya and Juglandoideae for the other genera. Iljinskaya (1990), however, recently established a new subfamily: Engelhardioideae for Engelho.rdtia. Lu (1982) points out that because of a great number of primitive characters occurring in Platycarya, the genus could not be derived from any other extant juglandaceous taxa but probably originated with the other groups from a common extinct ancestor. The present cytological data gives support to Manning's treatment. We are also in favor of Lu's supposition and suggest that basic aneu-ploid changes, both ascending and descending, from a common ancestor with the original basic number x - 7, took place during the course of early evolution of the Juglandaceae and led to the origin of taxa with x=6 and 8. Subsequent polyploidy based on these diploids occurred and brought forth polyploids of relic nature today, whereas their diploid progenitors apparently have become extinct. (2) Nanocnide pilosa Migo (Urticaceae). The chromosome number of this Chinese endemic is 2ri -24, with a basic number of x=12. An aneu-ploid series occur

关 键 词：植物区系 东亚 双子叶植物 染色体 

分 类 号：Q949.720.9[生物学—植物学] Q948.531