THE GENOTOXIC EFFECTS OF OZONE ON THE CHROMOSOMES OF ROOT-TIP MERISTEMS OF NORWAY SPRUCE (PICEA-ABIES (L) KARST)

Four-year old potted spruce trees (one clone of Picea abies (L.) Karst .) were exposed to two different levels of proportional addition of oz one to filtered air in open-top chambers for 101 days beginning in Jun e 1992. No visible symptoms resulted from these treatments. The classi fication of chromosomal aberrations in the metaphases was used as a te st system to characterize the impact on the root tips caused by ozone. In comparison to plants kept in charcoal-filtered air, spruce trees e xposed to ozone showed a significantly increased number of chromosomal aberrations in relation to the dose. The observed chromosomal abnorma lities consisted of chromosome stickiness, chromosome breakage and fra gments.