INDUCTION OF SISTER-CHROMATID EXCHANGES BY HEAVY-METAL SALTS IN ROOT-MERISTEM CELLS OF ALLIUM-CEPA L

Four heavy metal salts, nickel sulphate, mercuric chloride, cadmium su lphate and zinc sulphate, were tested for induction of sister chromati d exchange (SCE) in root meristem cells of Allium cepa. A simple modif ied Feulgen staining procedure was employed for SCE-analysis. Maleic h ydrazide and paraquat were included for comparison. An evaluation of g enotoxicity of the above test chemicals made on the basis of SCE-assay was found positive for all the test chemicals with exception of zinc sulphate which gave a weak positive result.