Karyotypic studies of five Paeonia ludlowii populations from China

karyotype of five Paeonia ludlowii populations from Tibet were analyzed in this study. P ludlowii was indicated to be a more primitive taxon. Each population possessed the same chromosome number as 2n=10, x=5, and the karyotypic formulae as 2n=8m + 2st. Population JZ possessed the most asymmetrical and evolutionary karyotype based on intrachromosomal asymmetry with the highest A(1) and lowest TF; According to the interchromosomal asymmetry with the value of A(2) and DRL, population CM was most asymmetrical. Detailed karyotype analysis showed that the length of SA was the main factor to group the different populations and to investigate the relationships among them. It suggested that when in a relatively narrow area, the karyomorphological variance of P. ludlowii mainly contribute to the hereditary property.