Abstract

ALVAREZ, Idioleidys et al. Toxic effect of Al³⁺ ion in the root tip of two Cuban rice cultivars (Oryza sativa L.). Rev. Int. Contam. Ambient [online]. 2013, vol.29, n.4, pp.315-323. ISSN 0188-4999.

Aluminium toxicity is an important factor limiting crop productivity in acid soils and toxic effects of this metal are primarily root related. The aim of this paper was to study responses to Al toxicity in two Cuban rice cultivars and the relation with Al localization at root of seedlings. Different AlCl₃ levels were employed to impose stress condition. Root apical segments were processed to optic microscopy by a Progressive Low Temperature Method (PLT) and they were included in Lowycril resin. The stained sections were viewed with Optic Microscopy (Zeiss) and photographed with Digital Camera Coupled to microscopy. Haematoxylin were employed to Al localization. Adventitious roots number was increased while the root elongation was reduced in seedlings exposed to Al. Different modifications were observed at the structure of epidermal and cortical cells in cross section. It provoked an increased at root diameter. These changes were accompanying by deformed roots and seedlings exposed to Al exhibited more root curvature than control seedlings and it could be consider a visual indicator to Al toxicity in rice plants. Differential Al localization and these results evidenced the toxic effect of Al in rice root cells and it evidenced that J-104 cultivar is more sensible to Al toxicity than INCA LP-7 cultivar.

Keywords : aluminium; toxicity; structural changes; rice.