A study of chromosome numbers of Petasites frigidus (L.) Fries and Petasites radiatus (J. F. Gmel.) Toman (Asteraceae) of Altai, Russia

Abstract

Petasites frigidus (L.) Fries had the stable chromosome number of 2n=60. However, P. radiatus (J. F. Gmel.) Toman had a mixoploidy since the majority of the mitotic metaphase cells showed 2n=86∼90 (83% metaphase cells studied) and 2n=30 (14% metaphase cells studied). Numerous data on chromosome numbers of Petasites reported in various species of the genus in 1970′s to 1980′s commonly reported 2n=60 by several authors should be rechecked and determined again.