TECHNOLOGY AND PRESERVATION AND STORAGE B IRCH POLLEN (BETULA-VERRUCOSA EHRH) - IN-VITRO GERMINATION OF NATIVE AND POLLUTED POLLEN - INFLUENCE OF ENVIRONMENTAL-FACTORS

Good preservation and storage of birch pollen (Betula verrucosa Ehrh.) is desirable for two reasons; for one it enables a deeper knowledge o f the biological state of the pollen and for the other, since birch po llen is a bio-indicator of air quality, its study under optimal condit ions (preservation and biological state) at the biological, structural , ionic and immunological level is essential for analysing the effect of atmospheric pollution on the pollen. For this reason this study has involved both pollen collected under natural conditions and pollen fr om urban sites (in situ). For a period of two and half years we have s tudied different methods of preservation and different storage tempera tures by in vitro germination tests on a 10% sucrose Heslop-Harrison m edium using rehydrated pollen. The best preservation is obtained with freeze-drying for half an hour and subsequent storage at 80 degrees C. The in vitro germination test on in situ pollen shows that the germin ation percentage is a reliable parameter for estimating the impact of atmospheric pollution on pollen because it varies in accordance with t he degree of pollution at the urban sites.