Abstract
The cytology of six taxa in five species of Limnophila viz. L. aromatica (n=17), L. hypericifolia (n=17), L. indica (n=17), L. chinensis (n=34), L. chinensis var. glabra (n=34) and L. conferta (n=34) has been studied. The chromosome numbers of these taxa except L. aromatica and L. indica are reported for the first time. 2n=34 in L. aromatica forms a new chromosome count. Secondary association of bi-valents has been encountered in L. aromatica and L. indica. On the basis of evi-dence from the secondary association, x=4 has been suggested to be the probable original basic chromosome number of the genus Limnophila. Somatic chromo-somes of all the six taxa have been studied and the karyotypes are characterized by small sized chromosomes.
