MORPHOMETRY OF POLLEN GRAINS OF SILVER BIRCH AS INDICATOR OF ECOCONDITION QUALITY
The aim of this study is to discriminate the quantitative morphological criteria of differences of one species pollen grains from different habitats in different types of planting. Morphometric measurements of 10 samples of Betula verrucosa Ehrh. pollen grains in the territory of Kyiv, Rivne regions of Ukraine and Nitra, the Slovak Republic were performed. Studied birches are from parklands, forest plantation, roadside plantations and plantations of special purpose - aerodrome «Borodyanka». Places of growth were estimated according to pollutant emissions from stationary and mobile sources, as well as the meteorological data (temperature, humidity, precipitation) in years of formation of pollen and birches flowering. Besides traditional morphological traits - the length of polar and equatorial axis - the angle of the outline of pollen grain in polar view, length of the internal diameter of apertures and apoporial field edge were also measured using SEM photos and software AxioVs40 V 4.8.2.0 (Carl Zeiss, Jena, Germany). These traits were selected based on the analysis of the structural features of Betula verrucosa Ehrh. pollen grains according to a Glossary of pollen and spore terminology (2006). Parametric Student's t-test to compare the morphological traits of pollen grains from Ukraine and Slovakia, simple and multiple regression analysis to evaluate the influence of anthropogenic factors and weather conditions on the morphology of birch pollen grains, cluster analysis for grouping the data were used. It was found that the current weather conditions and air pollution caused certain changes in the morphological and biological properties of silver birch pollen grains. The tendency to reduce the size of pollen grains was detect. The length of the polar axis is the most stable morphological traits and the length of the internal diameter of aperture is the most variable traits of pollen grains of Betula verrucosa Ehrh. The possibility of using selected morphometric traits of pollen grains of this species for indication of a condition of natural environment as more sensitive is considered. Our results have confirmed that there are statistically significant distinctions between populations of Betula verrucosa Ehrh. in morphological traits from different habitats, that is especially right for one species from the different countries. The proposed morphological traits of silver birch pollen grains can be used in the identification of the intensity of effect of negative environmental factors.