CONICET | Buscador de Institutos y Recursos Humanos

Despite the importance of algae and aquatic macrophytes at the base of the aquatic food webs, they are not commonly included in ecotoxicology research. Aquatic macrophytes convert solar energy and carbon dioxide into organic matter, produce oxygen, and provide habitat, food and oviposition sites for other organisms among other ecosystem services. Because of that, they must be protected from adverse agrochemical effects in order to maintain ecosystem functions and structure. Traditionally, persistent organic pesticides have been monitored, but current-use hydrophilic compounds have gained popularity and should be taken into account because they can induce acute and chronic effects in non- target organisms. The main objective of our work is to detect early stages of pollution by current- use pesticides in freshwater ecosystems using biomarkers in native aquatic species. We emphasize on fungicides and biochemical and genetic biomarkers in the aquatic macrophytes Bidens laevis and Myriophyllum quitense. Some fungicides have been detected in surface waters at concentrations higher than regulatory limit and it can be assumed that their massive use poses a risk for the environment. However, data of its effects are still scarce in theliterature. Azoxystrobin (AZX) belongs to a new class of widely-sold systemic fungicides. It has a low water-octanol partition coefficient (log Kow= 2.5), and its mode of action is the inhibition of mitochondrial respiration in fungi. In plants AZX is genotoxic, showing aneunogenic and clastogenic effects in B. laevis and M. quitense, respectively. Recent results show that it also causes oxidative stress, changes in certain enzymes associated with the carbon fixation as well as in photosynthetic pigments. Therefore, native species can suffer adverse effects that can contribute to decrease of genetic diversity of the populations which can ultimately reduce the fitness or drive to adaptation to contaminated environments.