Das Projekt "Untersuchungen der direkten und indirekten Wirkungen von Luftschadstoffen auf Wachstum, Qualitaet und Stoffwechsel landwirtschaftlicher Nutzpflanzen" wird vom Umweltbundesamt gefördert und von Universität Gießen, Fachbereich 08 Biologie, Chemie und Geowissenschaften, Institut für Pflanzenökologie (Botanik II) durchgeführt. Results from the ongoing European open-top chamber projekt 'Effects of air pollutants on plants: pysiological and biochemical modifications' have shown that ozone (O3) is the predominating pollutant during the growing season of agricultural crops. Recent research at Giessen has identified spring wheat (Triticum aestivum) as a very sensitive species to O3. Also, several other groups working under the European Protocol used this agronomically important species for their pollutant effect studies during the past seasons. In order to get insight into the mechanisms of the O3 effects it is planned in an additional experiment (1991 growing season) to investigate specific metabolic parameters in foliage of wheat plants. Increase in peroxidative processes as a result of enhanced formation of active oxyradicals are discussed as possible primary causes of pollutant damage in plant tissues. Thus, special emphasis will be laid on the effects of O3 on the components of the antioxidative system of plants.