SEASONAL-CHANGES IN THE ACTIVITIES OF APOPLASTIC, CYTOPLASMIC, IONICALLY AND COVALENTLY BOUND ISOPEROXIDASES FROM NORWAY SPRUCE (PICEA-ABIES (L) KARST) NEEDLES - A COMPARISON BETWEEN 3 COLLECTION SITES WITH DIFFERENT AMBIENT OZONE CONCENTRATIONS

Apoplastic, cytoplasmic, ionically and covalently bound isoperoxidases were investigated from needles of Norway spruce (Picea abies (L.) Kar st.) and a pronounced genetic variability of the isoenzyme pattern was found. The enzymatic activity of each group of isoperoxidases was det ermined between November 1989 to November 1990 from needles of three l ocations (Velmerstot, Glindfeld, Haltern) with different ozone concent rations. Apoplastic peroxidases of needles from trees grown in Velmers tot and Glindfeld showed up to two-fold higher activities than the sam e group of peroxidases from Haltern. Based on the recorded increased o zone concentrations in Velmerstot and Glindfeld a positive correlation between the activity of the apoplastic peroxidases and ambient ozone concentrations at the different locations could be demonstrated. A put ative role of the apoplastic peroxidases as a bioindicator for air pol lutants is discussed.