Karyological study of <i>Ageratum conyzoides</i> Linn. and <i>Eclipta alba</i> (L.) Hassk from the Asteraceae family

The comprehensive karyological studies were undertaken for Ageratum conyzoides Linn. and Eclipta alba (L.) Hassk of the Asteraceae family in Bangladesh. The present report deals with somatic chromosome numbers, total chromosome length, arm ratio, centromeric position, Stebbins classification along with other karyotypic parameters, distribution pattern, and percentage of AT- and GC-rich DNA sequences with orcein, chromomycin A3 (CMA), and 4′,6-diamidino-2-phenylindole (DAPI) stainings. somatic chromosome numbers of 2n=40 and 2n=22 were observed in A. conyzoides and E. alba, respectively. The total diploid chromosome length of A. conyzoides and E. alba was 142.3 and 86.5 µm, respectively. Karyological data of both species suggested 1A karyotype. A. conyzoides showed only CMA bands whereas E. alba had both CMA and DAPI bands. Except for somatic chromosome number, the karyomorphological information and fluorescent banding pattern of A. conyzoides and E. alba are reported for the first time.