Abstract
The study considers the issues of introduction and reintroduction of the Red Book species of checker tree in the system of decorative gardening, forest protection, and forest ecosystems. That is why the purpose of the study was to monitor the green corridors of rural and urban ecosystems of the forest-steppe zone of Ukraine, to investigate and select the best forms of checker tree in terms of morphological characteristics and physiological properties for promising areas of distribution and conservation in the form of pure and mixed plantings. The following methods were used in the research: route, field, biometric, laboratory, comparative analysis, mathematical and statistical. New forms of checker tree were introduced, studied in in situ and ex situ conditions, and selected for the prospects of their further introduction and reintroduction into the ecological network of Ukraine and conservation to activate trophic, phoric, and other types of biotic interactions in a single territorial ecosystem. Sparsely distributed biotypes of Torminalis glaberrima (Gand.) Sennikov & Kurtto f. Intermedia Kossetz were found in the zone of green corridors of rural and urban ecosystems of the forest-steppe zone of Ukraine. Some specimens of these biotypes were identified as valuable material for introduction into the system of fruit and ornamental gardening, including parks and monuments of landscape art, as well as natural monuments, protected tracts, sanctuaries and reserves of pure and mixed plantings, alleys, forest reclamation strips, etc. It was established that the elements of originality of the selected forms of checker tree – Eva, Podolianochka and Slavka – are the specificity of the crown shape, which determines the level of productivity, small and medium growth force, normal reaction to pruning (which affects the size and yield of fruits), high degree of flowering (60-80%), increased fruit size (diameter of more than 2 cm), increased fruit weight (1.8-2.1 g), increased number of fruits on the stem (≥20 units), a pleasant and harmonious taste of fruits, high quality of fruits, lack of periodicity in fruiting in nature and in culture, high xenogamy (69-75%), high yield of fruits from the plant, increased winter hardiness (7.5 pt.), high drought resistance (8 pt.) and resistance to pests, including pear leaf blister mite (7-9 pt.). The findings can be used in the future to replenish pure and mixed plantings in the ecological network of Ukraine