Stress response across levels of organization in the terrestrial isopod Porcellio scaber and the duckweed Lemna minor: a mechanicistic approach

Three years of interinstitutional and interdisciplinary study on metal toxicity financed by Ministry of Education, Science and Sport (Project Code: J1-3186-0487-01) is a basis for our future direction in the same field and with the same group of researchers (http://www.fgg.uni-lj.sisdrobne/DDrobne/ProjectToxicity/). We will focus the research on mechanicistic understanding of stress response across levels of biological organization what improves our understanding of the risks posed to organisms by pollutants, unfavorable environmental conditions and pathogenic agents. The aim of our work is to determine stress response across levels of biological organization in two most studied organisms in environmental toxicology: a terrestrial isopod Porcellio scaber (Isopoda, Crustacea) and a duckweed Lemna minor (Lemnaceae). Understanding of stress response is a basis for selecting proper suite of biomarkers for bioassessment and biomonitoring of polluted environments. Stress effects are usually expressed first at the molecular or cellular level and can be propagated upward trough increasing levels of biological complexity. Physiological, histological, behavioral, reproductive responses can serve as an intermediate or pivotal response point by which the mechanistic basis of effects at lower levels can be causally linked to ecologically relevant measures at the population and community levels. Mechanicistic understanding of stress response is possible only when it is studied across levels of biological organization ranging from molecular to organism level response. Stress response study in our work will include endpoints on biochemical, cellular, histological, physiological (energetic-based approach) and behavioral levels in terrestrial isopod Porcellio scaber (Isopoda, Crustacea) and biochemical, cellular, histological and physiological endpoints in a duckweed Lemna minor (Lemnaceae). We will study stress response induced by metals (cadmium, mercury, copper and lead) and organophosphorus pesticide, the diazinon in laboratory experiments. At the same time, biomonitoring of different polluted locations in Slovenia (Idrija, Žerjav, Radlek) will be carried out. Biomonitoring results will be prossed by GIS tools. A suite of biomarkers for each polluted location will be selected on the basis of laboratory results. The objective of bioassessment and biomonitoring is to describe the state of the environment and to link cause and effect where there is degradation before remedial action or punitive measures are taken.