The Taxon Cnidium monnieri of Umbelliferae as a Cytological Aberrant Species

Abstract

Cytological studies in Cnidium monnieri of the family Umbelliferae have shown variability in chromosome number in the somatic cells from the same root tip, and the PMCs also exhibited variability in chromosome number and pairing behaviour. The taxon has shown stabilization at chromosome number 36 although a lower number 18 or higher number 72 has also been observed. It is considered to be a hybrid involving closely related taxa. The genetic control for regulation of pairing of chromosomes is either yet to be evolved or it has undergone a mutation which is reflected in multivalent formation in a few PMCs.