Three different techniques were applied to analyze the patterns of longitudinal chromosome differentiation in five Sesbania species (S. exasperata, S. punicea, S. sesban, S. tetraptera, and two different geographical populations of S. virgata). For all the species investigated, the prophase chromosome condensation was always proximal. After staining with the fluorochromes chromomycin A(3) and DAPI, each karyotype revealed two or four CMA(+)/DAPI(-) heterochromatic blocks, apparently corresponding to the nucleolus organizing regions. However, in S. virgata two or four CMA(+) bands were observed, depending on the population studied. No DAPI(+) bands were observed. C-banding showed the most diversified patterns, being a more useful technique to distinguish karyorypes of Sesbania species. The largest amount of heterochromatin was observed in S. virgata (subgenus Daubentonia) whereas the smallest was found in S. sesban (subgenus Sesbania).52416719710
