Testkammerverfahren zum nachweis phytotoxischer immissionskomponenten
Abstract To identify the presence of phytotoxicants in the air, particularly in areas with several pollutants, portable exposure chambers have been developed in which plants are exposed to filtered and unfiltered air. These chambers consist of a plexiglass cap covering the plants to be exposed and a box below containing air filter, blower, and watering system. An experimental unit includes at least two such chambers. Ambient air is passed directly through the test chamber, whereas it is filtered before entering the control chamber in order to remove any phytotoxicants present. By comparing plant reactions in both chambers, effects of pollutants can be accurately identified. Individual pollutants are identified by using special filtering systems and with combinations of indicator plants with differing resistance. A filter material coated with silver and silver-oxide is used to remove the most important pollutants, SO 2 , HF and HCl. Leaf injuries on the tobacco variety BEL W 3 , which is very sensitive to oxidants, can be prevented by using this filter material. These exposure chambers can be used to carry out fumigation experiments both in the field and in climatic chambers as well as to test pesticides.