Karyotype Analysis in Japanese Cichoricae II

Abstract

1) The karyotypes of three species of Sonchus, one species Hieracium and one species of Prenanthes are reported.
2) The chromosome numbers of Hieracium umbellatum var. japonicum and Prenanthes Tanakae are here reported for the first time.
3) Sonchus oleraceus seems to be an amphidiploid considering from the karyotypical stand point. But the Stebbins' opinion that Sonchus oleraceus may be an amphidiploid containing eighteen chromosomes of S. asper plus the fourteen chromosomes of S. Tenerrimus can not be confirmed from this karyotype analysis.