Cytogenetic Characteristics of Weeping Birch (Betula pendula Roth) Seed Progeny in Different Ecological Conditions

The present study of cytogenetic characteristics in seed progeny of woody plants in stress and no-stress conditions is important for better arrangement of green spaces in cities and reforestation on anthropogenically polluted territories because it allows to select maternal trees producing seeds resistant to stress factors. The following cytogenetic characteristics of the root meristematic cells of weeping birch (Betula pendula Roth) seedlings were studied: mitotic and nucleolar activities, frequency and spectrum of pathological mitosis, frequency of persistent nucleolus in mitosis. Seeds for this study were collected from maternal trees growing in anthropogenically polluted and ecologically safe areas of the Central Black Earth Region of Russia. Cluster analysis revealed four clusters of seedlings on each territory: “mutable”, “low-mutable” and two clusters with intermediate characteristics. The characteristics and differences of these clusters are described in the article. _____________________________________________________________________________________________________________