Abstract:
The chromosome number of 3 menispermaceous species——
Stephania cepharantha Hayata,
Cyclea racemosa Oliv. and Cocculus orbiculatus (L.) DC from China are reported. They are 2
n=22, 24 and 52, respectively. This exhibits the basic chromosome number of Menispermaceae are
x=11,12 and 13.There is B-chromosome occurring in some individuals of part populations of
S.cepharantha.
C.orbiculatus should be a tetraploid.The meiosis of
C.orbiculatus is observed and its whole process is normal.The pollen grain fertility of
C.orbiculatus is normal also.