KARYOTYPE DIVERSITY AND GENOMIC VARIABILITY IN SOME INDIAN TREE MANGROVES

Investigation on karyotype and genomic characteristics of 11 Indian tr ee mangroves belonging to the family Bignoniaceae, Malvaceae, Myrsinac eae, Rhizophoraceae and Sterculiaceae revealed wide genetic variation. Numerical and structural alteration of chromosomes at intergeneric an d interspecific level were manifested in the species specific genome l ength, volume and form percentage of the karyotype. Somatic chromosome number varied from 2n = 26 in Thespesia populnea of Malvaceae to 2n = 44 in Aegiceras corniculatum of Myrsinaceae. The members of Rhizophor aceae and Sterculiaceae showed 2n = 34, 36, 38 chromosomes in the root tip cells. Correlation coefficient studies among the cytological para meters showed significant progressive interdependence within the speci es. Critical differences in the average genome length and genome volum e showed significant variation.