A STUDY OF PHYSICAL an‎d ANATOMICAL CHARACTERISTICS OF THE HEAVY METAL ACCUMULATION OF JUNCUS RIGIDUSDESFONTAINES, 1798 (FAMILY, JUNCACEAE)IN BASRAH PROVINCE, SOUTHEREN OF IRAQ

This study was carried out to determine the heavy metal accumulation ofJuncus rigidusDesfontaines,1798 from three different regions of the Basrah Province in Southern of Iraq. Specifically, the concentrations of lead, nickel, and cadmium were determined in the roots, culms and leaves of the plant. The results indicated that the highest accumulation of the heavy metal was recorded in lead (Pb) 12.50± 3.58 mg kg-1and then in nickel (< 0.30). The lowest value was recorded for cadmium (< 0.05).As well, lead concentrations in J. rigidusvariedin different locations and parts of the plant from undetectable in control to 12.66, 19.33, and 9.80 mg kg-1in leaves, culm, and roots respectively from Station 2, and 10.76, 12.66, and 9.50 mg kg-1 in Station 3. The values of translocation factor (TF), bioconcentration factor (BCF), and Biological Accumulation Coefficient (BAC)were greater than>1 used to the ability of J. rigidusfor both phytoextraction and phytostabilization. The anatomical analysis showed that heavy metal accumulation in plant tissues led to a reduction in root and culm thickness; in pollutedarea it has been found that cortex and intercellular spaces in aerenchyma layers were deceased in size, whereashigh pollutionlevels were observed in vascular bundles, which were smaller, and had increased sclerenchyma, as well as appeared more black or dark color compared to the specimens grown in the control area.