摘要
首次报道了我国伞形科１０个特有属９种１变种１４个居群的核型，染色体基数分别为ｎ＝６，８，１０和１１，核型类型有２Ａ，３Ａ和４Ａ三种类型。根据各属的核型演化水平并结合其花粉形态，初步确定东俄芹属（Ｔｏｎｇｏｌｏａ）、环根芹属（Ｃｙｃｌｏｒｈｉｚａ）、明党参属（Ｃｈａｎｇｉｕｍ）和川明参属（Ｃｈｕａｍｉｎｓｈｅｎ）是古特有属，其余各属则处于中等或较高的演化水平上。同时初步讨论了各特有属在伞形科分类系统中的核型演化关系并比较了各主要分布区之间核型的演化水平，发现横断山地区不仅特有属数目高，染色体基数变化大，且集中了核型较为原始和演化程度很高的类群，极可能是伞形科特有属的起源和分化中心。
Nearly 21 endemic and semi- endemic genera of Umbelliferae occur in China,in which 15 genera are distributed in Sino- Himalayan forest subkingdom and 6 genera in Sino- Japan forest subkingdom. The present paper first report the karyotypes of 10 endemic genera(including 1 semi-endemicgenus) with chromosome numbers n=6,8,10,11. The karyotype formulae are as follows:Tongoloa silaifolia(de Boiss. ) Wolff 2n=16=10m +4sm+2sm￣sat(Qinbashan,Shaanxi); Notopterygium incisum Ting ex H. T. Chang 2n=22=18m+2sm+2sm￣sat(Songpan,Sichuan);Cyclorhiza waltonii(Wolff) Sheh et Shan 2n = 22=12m+10sm(Lijiang,Yunnan);Vicatia bipinnata Shan et Pu 2n=22 = 16m+4sm+2st￣sat(Barkam, Sichuan); Changium smyrnioides Wolff 2n=20 = 10m+6sm+4st(Xianning,Hubei)and 2n = 20= 10m+4sm+4st+2st￣sat(Nanjing,Jiangsu);Chamaesium thalictrifolius Wolff 2n= 12= 4sm+6st+2st￣sat(Songpan,Sichuan);Carlesia sinensis Dunn 2n= 22=14m+8sm(Qingdao,Shangdong),2n = 22=14m+6sm+2st￣sat (Yantai,Shangdong)and 2n=22 = 16m+6sm(Dandong,Liaoning);Nothosmyrnium japonicum Miq.var.sutchuensis de Boiss. 2n=20= 4sm+16st(Wulong,Sichuan); Chuanminshen Violaceum Sheh et Shan 2n=22= 10m+10sm+2st(Dangyang,Hubei) and 2n = 22 = 12m+6sm+2sm￣sat+2st(Jintang, Sichuan); Arcuatopterus linearifolius Sheh et Shan 2n=22=4m+4sm + 2sm￣sat+12st(Binchuan,Yunnan).The karyotypes of 7 genera belong to“2A”except those of Arcuatopterus“3A”,Chamaesium and Nothosmyrnium“4A”. By analysing the karyotypic evolution and combined with pollen morphology of 8 endemic genera(M.L.Sheh 1987),it is clear that Tongoloa,Cyclorhiza, Changium and Chuanminshen might be paleoendemic , and the others are intermediate genera in different evoluti on levels. Based on the comparison of karyotypes among the main floristic areas of 10 endemic genera,it is found that many endemic genera with the most primitive and the most advanced are concentratd in Hengduan-Shan region of Sino-Himalayan forest subkingdom,therefore a conclusion might be obtained that the center of origin and diversity of endem ic genera of Umbelliferae is in Hengduan-Shan region.
出处
《植物资源与环境》
CSCD
1995年第3期1-8,共8页
Journal of Plant Resources and Environment
基金
国家自然科学基金
关键词
伞形科
特有属
核型
地理分布
Umbelliferae
endemic genus
karyotype
geographical distribution
