Karyotype in 20 Populations Belonging to 10 Species of Allium from Southwest China

Chromosome number and karyotype in 20 populations belonging to 10 species of Allium from China were reported in this paper,they were A.omeiens,A.wallichi,A.macranthum,A.tuberosum,A.sikkimense,A.cyaneum,A.xichuanense,A.rude,A.chrysanthum and A.eusperma.Based on Stebbins’karyotype classification there were 2A,2B and 2C types;the basic chromosome numbers were 7,8 and 11;satellite heterozygosis and polyploidy were common in these species.The results also show:the asymmetry index of A.omeiense was related to the altitude;pentaploidy A.macranthum evolved along with the fission and deletion of short-arms of st chromosome.Combined with the karyotypical,morphological and reprductive trait,the evolutional and systematical questions of some taxa were discussed.