The Effect of Some Heavy Metals Accumulation on Anatomical and Physiological Characteristic of The Submerged Macrophyte Vallisneria Plant
The degree of contamination by heavy metals (Hg and Pb) on Vallisneria plants has been studied. Plant was exposed to metal treatments of Hg and Pb for three weeks. Leaves were harvested for studying anatomy and analyzing metal accumulation. Accumulation of Hg and Pb in all parts of the plant increased significantly with an increase in applied metal concentration. Results showed the maximum heavy metal concentrations, in the root and minimum heavy metal concentrations in the leaves. Total chlorophyll content increasing concentrations of the heavy metal. In Hg was 5.50%, while in the Pb found the lower effect on total protein research to 4.22 % at 15 mg/l concentration.
Anatomical analyses of Vallisneria leaves revealed several changes in the leaves of plants submitted to contaminated treatments. The leaves of plants exposed to contamination presented modified anatomical characteristics. Exposure to heavy metals leads to a reduction in the size of blade thickness, number of conducting elements, reduced cell size of the epidermis and aerenchyma tissue. Leaves undergo changes in size, shape and arrangement of leaf blade and cortical parenchyma cells as well as reduced in vascular bundles.
Keywords� Aquatic plants, Vallisneria, heavy metal, chlorophyll, anatomy.