Effects of aluminium ion on root growth, cell division, and nucleoli of garlic ( Allium sativum L.)

The effects of different concentrations of aluminium chloride on root growth, cell division, chromosome morphology and nucleoli in root tip cells of garlic ( Allium sativum L.) were studied. The concentrations of aluminium chloride (AlCl 3) used were 10 −5, 10 −4, 10 −3, 10 −2 and 10 −1 m. Aluminium chloride inhibited root growth and caused mitotic irregularities, including c-mitosis, anaphase bridges, and chromosome stickiness. Nucleolar material was extruded from the nucleus into the cytoplasm. Extrusion was observed in inner root meristem and root cap cells. The poisoning by Al 3+ of the root tip cells of Allium sativum may result from the uptake and accumulation of Al and inhibition of Ca uptake, distribution of physiological activities of calmodulin (CaM) and the inhibition of some enzyme reactions.