Abstract: | The present paper reports the chromosome number and karyotype of the genus
Hydrilla. H. verticillate was found to have 2n=16. The karyotype is 2n=16=6m+6sm+
4st. No difference between the male and the female was found in the work. H. verticillata
var. roxburghii Casp. has the somatic chromosome number 2n=24, and its karyotype is 2n=
3x=24=9m+9sm+6st. The variety may be a autotriploid. The karyotype of the genus isobviously bimodal, with No. 1-5 in the first group and 6-8 in the second group. |