Karyotype Diversity in Three Medicinal Piper Species in Bangladesh

Karyotypes of three Piper species viz. P betle L., P longum L., and P retrofractum Vahl were studied with a conventional staining and a fluorescent banding. P betle, P longum, and P retrofractum possessed 2n=68, 2n=48 and 2n=72 chromosomes in root tip cells, respectively. Chromosome number of P retrofractum (2n=6x=72) is the first report. The three species of Piper showed distinct chromomycin A(3) (CMA)- and 4',6-diamidino-2-phenylindole (DAPI)-band patterns based on the number, location, and size of CMA-and DAPI-bands. The several chromosomes fluoresced overall by CMA or DAPI and these fluorescent bands will be a good marker for chromosome study. The three species were different in respect of conventional karyotype and fluorescent banding pattern. In three Piper species, the comparative karyotype analysis of fluorescent banded chromosomes might suggest that chromosome diversity occurs in aneuploidy and polyploidy.