蒙新荒漠两侧丽豆属对子种的细胞地理学研究  

THE CYTOGEOGRAPHY STUDY OF ONE PAIRING SPECIES OF CALOPHACA FISCH.IN WEST AND BAST SIDES OF MONGOLIAXINJIANG DESERT

作　　者：李思锋[1] 常朝阳[1] 黎斌[1] 徐朗然[1] 

机构地区：[1]中国科学院陕西省西北植物研究所

出　　处：《西北植物学报》1998年第2期246-251,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金;陕西省科学院青年科学基金

摘　　要：中国丽豆和新疆丽豆是蒙新荒漠两侧豆科植物区系中一对较为重要的间断分布的对子种。中国丽豆分布于黄土高原东部的局部地区，而新疆丽豆分布于新疆塔城一带和西天山山脉。从细胞地理学角度对它们进行了研究，结果表明：中国丽豆为二倍体，核型公式为２ｎ＝２ｘ＝１６＝１２ｍ＋４ｓｍ；新疆丽豆为四倍体，核型公式为２ｎ＝４ｘ＝３２＝２４ｍ（４ＳＡＴ）＋８ｓｍ，两种均为“２Ａ”核型，属的染色体基数ｘ＝８。中国丽豆和新疆丽豆虽然在形态上比较接近，但在核型上的差异明显，应为两个独立的种。中国丽豆是黄土高原比较典型的第三纪古特有种。第三纪末以来亚洲内陆持续旱化、沙漠化和荒漠化不断扩大，这可能是造成其地理残遗的主要因素。而新疆丽豆在倍性上属于比较进化的四倍体，这可能是对其生境变化适应的结果。由于丽豆属在中亚山地集中分布６种１变种，约占全属８种１变种的７７％，因此中亚是本属的现代分布和分化中心。オ獵alophaca sinica and C.soongorica are one pair of important disjunctive corresponding species in MongoliaXinjiang leguminous floristics.The former is endemically distributed in east parts of Loess Plateau,and the later is distributed in Tacheng of Xinjiang of China and some other Middle Asia areas.In this paper,we dealed with their chromosome numbers and karyotypes,and gave a brief discussion on their phytogeography.C.sinica,located to the east of the MongoliaXinjiang desert,is diploid with karyotype formula of 2n=2x=16=12m+4sm,while C.soongorica,to the west of the desert,is tetraploid with karyotype formula of 2n=4x=32=24m(4SAT)+8sm.Their karyotype symmetries are “2A” types.Thus,the basic number of Calophaca is x=8,and this basic number is correponding with that of Caragana and Chesneya.In phytogeography,Calophaca sinica is an old endimics to east central part of Loess Plateau,and a geographical relict of Tertiary period,while C.soongorica is a new differentiated species adopted to its colder environment,its distributed area being on the north border of the distribution of the genus.Because 6 species and 1 variety,about 77% of the total 8 species and 1 variety,of Calophaca is distributed in Middle Asia mountains,this area must be the modern distribution and differentiation center of this genus.

关 键 词：细胞地理学 丽豆属 对子种 中国丽豆 新疆丽豆 

分 类 号：Q949.751.9[生物学—植物学]