| Abstract: | The present paper reports karyotype analysis of Cephalanthera erecta and C. falcata from Lushan, China. (1) The karyotype formula of C. erecta is 2n=34=10m+ 14sm+
10st. C. falcata has two cytotypes: type A is 2n = 34 = 8m + 16sm + 10st, while
type B is 2n = 34 = 8m + 22sm + 4st. The type B is a translocation homozygote
derived from the type A by chromosomal structural reorganization, which involved a
translocation between the short arms of the 1st pair of chromosomes and the long
arms of the 3rd pair. The type B is similar to the type A in morphological characterissties. (2)In the light of Stebbins’ classification of karyotypic asymmetry, three karyotypes of C. erecta and C. falcata belong to “3C”. Such an asymmetrical karyotype
in a primitive genus like Cephalanthera of Orchidaceae may be of great significancefor a discussion on evolution and deserves a further study. |
