C-Banding and Sister Chromatid Exchanges in Three Species of the Genus Allium (A. Cepa, A. Ascalonicum and A. Sativum)

SUMMARY

C-banding and differential staining of sister chromatids by the FPG technique after BrdU incorporation into DNA was performed in Allium cepa, Allium ascalonicum and Allium sativum. Despite the similarity in the karyotypes, the study of C-banding pattern of these three species of the genus Allium revealed important differences existing between A. sativum (Section Allium) and the other two species (Section Schoenoprasum). Finally, a lower than expected frequency of SCEs has been observed in A. ascalonicum, on the basis of its DNA-content and pattern of constitutive heterochromatin.