Fluorescent banding pattern analysis of eight taxa of Phaseolus and Vigna in relation to their phylogenetic relationships.

Phylogenetic relationships among eight taxa of seven species of Phaseolus and Vigna (Phaseolus angularis, P. aureus, P. calcaratus, P. coccineus, P. vulgaris, Vigna sesquipedalis and V. sinensis; 2n = 22 each) were studied by the fluorescent chromosome banding technique. Preparations of somatic metaphase chromosomes of each taxon were sequentially stained with Giemsa, GC-specific fluorochrome chromomycin A3 (CMA) and AT-specific fluorochrome 4'-6-diamidino-2-phenylindole (DAPI). On the basis of the fluorescent banding patterns of the 22 chromosomes of each taxon, P. angularis, P. coccineus (from China and Korea) and P. vulgaris were grouped into one group ("Phaseolus group"), P. aureus and two Vigna species were grouped into another ("Vigna group") and P. calcaratus was grouped in an independent group.