UPTAKE OF HEAVY METALS BY TOMATO PLANTS (Lycopersicum esculentum Mill.) AND THEIR DISTRIBUTION INSIDE THE PLANT
The aim of this study was to examine the concentration of total and available forms of heavy metals (Ni, Cr, Cu, Zn, Pb and Mn) in the greenhouse soils as well as the distribution of these metals in the different parts of tomato plants grown on these soils. Atomic Absorption Spectroscopy (AAS) was used to determine heavy metals concentration. The concentration of available forms of all examined heavy metals in the soils and in tomato fruits were low, although the total concentration of hazardous heavy metals Ni and Cr in soils exceeded the maximum permissible values, prescribed by legislative rules in Bosnia and Herzegovina. The reasons for the low uptake of heavy metals by tomato plants are mainly related to the chemical properties of soil which are not favorable for heavy metal availability. In addition, the results of this study also showed that the accumulation of all examined heavy metals especially Cr and Ni were much higher in the roots than in the fruits. The low accumulation of heavy metals in tomato fruits is the result of synergy of different plant defense mechanisms that limiting or reducing heavy metal transport from root to fruits.