Abstract: This is the first report of the chromosome karyotype of P. anomala from the Altai populations. The populationssampled from the Altai region of Xinjiang , China , are diploid ( 2n = 10) , with the 2A type karyotype and the karyotypic
formula of 2n = 2x= 10 = 6m+ 2sm+ 2st . Based on karyotypic and asymmetric parameters, i . e ., mean arm ratio , ratioof longest􊄯shortest chromosomes (L1/Ln ) , coefficient of karyotypic overall asymmetry (CKOA) , it was found that therewas no apparent differentiation in karyotype features among all the three sections of the genus Paeonia , although someslight karyotypic differences were found between the woody section ( Sect. Moutan DC .) and the herbaceous sections(Sect . Onaepia Lindley and Sect. Paeonia) . The diploid status of the P . anomala populations , revealed in this study, implies that the species, assumed as interspecific hybridization origin , may add to the handful examples of homoploid hybridspeciation in angiosperms .

Key words: Paeonia