Growth responses of tomato plants (Solanum lycopersicum) to aluminium and nickel from nanoparticle suspensions and ionic solutions

Abstract

We have recently described the fate of gamma-alumina-based nanomaterials containing Ni and non-nanometric Ni on soil from lysimeters. The objectives of the present work were to evaluate the effects of Al and Ni from nanomaterials, aluminas and non-nanometric Ni on seedlings elongation and on tomato plants growth; the quantification of Al and Ni incorporation in seedlings, by neutron activation and a preliminary analysis of nutrient elements present in stems and leaves of plants, by scanning electron microscopy. Non-nanometric Ni inhibited root and hypocotyl elongation in a concentration-dependent manner, while acid alumina and two nanomaterials caused greater elongation of seedlings. Ni and Al incorporation was demonstrated, except for one nanomaterial. In experiments with plants, they were grown in garden soil alone and mixtures also containing soil from Gan Gan, Chubut province, Argentina. The fresh and dry weight of plants aerial parts were significantly lower under treatments in different soil mixtures with Ni(NO3)2.6H2O (190 mg/L) compared to the Control plants (0.33 ± 0.02 vs 0.49 ± 0.10 and 0.005 ± 0.0001 vs 0.007 ± 0.003 g/plant respectively). It was demonstrated that non-nanometric Ni was toxic to the plants. More trials should be carried out to elucidate whether nanomaterials can be related to alterations on nutrient elements and be toxic to tomato plants.