This paper presents the phenology of seven taxa of the genus Magnolia L., pollen biology on germination and storage conditions, seed productivity, germinating ability of seeds and its dependence on stratification and germination conditions. It has been found that M. kobus DC, M. kobus var. boreales Sarg., M. obovata Thurb., M. officinalis Rehd.in cultivated condition produce pollen at a low viability rate (9.4 -31.7%). Real seed productivity of the taxa being studied is less than their potential productivity. However, M. obovata, M. officinalis and M. tripetala are characterized by high seed germinating ability, up to 94%. Optimal germination conditions for seeds of M. tripetala, M. officinalis and M. obovata require protected ground (greenhouse) and stratification at 4ºC during 30 days. The high germinating ability of M. sieboldii seeds in the open ground is explained by stratification duration and temperature required for this species. Sarcotesta effects on higher seed germinating ability have been observed in M. obovata only.

We studied the relationships between morphometric parameters of leaves of Rhododendron mucronulatum and climate features at the northern limit of its distribution. A great morphological diversity in leaf shapes, including strong deviations from the typical lanceolate and acute leaf shape was revealed. We found that the frequency of an elliptic shape with obtuse apex is the result of morphological adaptation to particular climatic conditions and that the diversity of leaf morphological features were strongly correlated with temperature and annual precipitation. The climatic parameters of the winter period were found to be more important for determining the leaf shape than the climate during the growing season.

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The size of Rhododendron sichotense seeds and exotesta cells from 20 populations were studied using a scanning electron microscope (SEM). The results of a correlation analysis showed that seed size depends on bioclimatic factors. As a species marker, we used the exotesta cell elongation coefficient. This characteristic was unresponsive to environmental variables, demonstrating its taxonomic significance. In the centre of the species range, the samples had an exotesta cell elongation coefficient that was typical for the species, but in samples from the far northern and southern parts of the range, where the distribution of R. sichotense meets that of of R. dauricum L. and R. mucronulatum Turcz., respectively, the value of the exotesta cell elongation coefficient was intermediate between these species. Therefore, the exotesta cell elongation coefficient can be recommended for use in the detection of hybridisation areas.