Abstract:

The chromosomes number and karyotypes for an important medicinal plant , Erigeron breviscapus ( Vant. ) Hand. -Mazz. , in wild populations from Yunnan were reported in this paper. Two kind of ploidy levels were observed within two populations of the species. (1) Cangshan population: the karyotype formula of the diploid type is 2n = 2x = 18 = 4m+ 10sm+ 4st and 2n = 3x = 27 = 6m + 12sm+ 9st for triploid, (2 ) Yangjiaping population: the karyotype formulaof the diploid type is 2n = 2x= 18 = 6m + 10sm+ 2st and 2n = 3x= 27 = 3m+15sm+9st for triploid. The triploid type of E. breviscapus was discovered for the first time. Morphological characteristics of the triploid individuals suggest that E. breviscapus has a potential for fostering a better breed .

Key words: Erigeron breviscapus