Abstract: Nearly 32 species of Angelica occur in China, taking up one third of total species number of the genus in the world, with 12 species in Sichuan. In the present paper karyotypes of 8 species from Sichuan are first reported with x = 11. The parameters of chromosomes of 8 species are given in Table 1 and the karyotypes are shown in Plate 1, 2. The karyotype formulae are as follows: A. valida Diels K(2n) =22=20m+2sm (Wulong Xian, alt. 1900m); A. dielsii Boiss. K(2n) =22= 18m+2sm^sat+2sm (Songpan Xian, alt. 3000m); A. laxifoliata Diels has 2 kinds of karyotypes in 3 populations: K(2n) =22= 18m+4sm (Hanyuan Xian, alt. 1900m) and K(2n) =22= 16m+6sm (Songpan Xian, alt. 2500m and Baoji in Shaanxi, alt. = 1500m); A. setchuensis Diels K (2n) = 22 = 16m+2sm^sat+4sm (Songpan Xian, alt. 2800m); A. maowenensis Yuan et Shan K(2n) =22= 16m+ 6sm (Songpan Xian, alt. 2800); A. chinghaiensis Shan ex K.T.Fu K (2n) = 4x= 44 = 36m+8sm (Songpan Xian, alt. 3500m); A. Sinensis (Oliv.)Diels K(2n) =22= 14M+8sm (Songpan Xian, alt. 2900m); A. omeiensis Yuan et Shan K (2n) = 22 = 10m+2sm+ 10st (Mt. Omei, alt. 2100m). The karyotypes of A. valida and 2 populations of A. laxifoliata belong to “1A” and those of one population of A. laxifoliata and the rest 6 species “2A”. By analysing the correlation between the karyotypic symmetry and vertical distribution of A. laxifoliata and A. chinghaiensis, it is considered that as altitude rises, the karyotypic asymmetry and ploidy increases. Comparing with the karyotypes of other species distributed in Northeastern China and Japan previously reported, the karyotype of A. valida with oblong-ovoid fruits and 1-2-pinnate leaves is most primitive and that of A. omeiensis with nearly rounded fruits and 3-ternate-pinnate leaves is most advanced in Angelica. Based on the fact that many species including the most primitive and the most advanced species are concentrated in Sichuan, it may be suggested that the center of origin and diversity of Angelica be inSichuan characterized.

Key words: Angelica, Karyotype, Geographical distribution, Sichuan