Studies on Terrestrial Herbaceous Plants Tolerance to Excess Heavy Metals: Methodological Approach

Plant tolerance to heavy metals is а scientific issue attracting significant attention due to the possible use of tolerant plants for phytoremediation purposes as well as due to the fact that the molecular mechanisms of this phenomenon are not clear enough. Despite of the increasing volume of research on the problem, the available information in many cases is incomplete and/or difficult to compare with other studies because of the significant differences in the experimental designs, range of used metal concentrations, exposure time, etc. In this review-paper both the advantages and limitations of the used experimental designs as well as the methods for evaluation of heavy metal tolerance are briefly discussed.