Skryaga V. Economic and biological evaluation of cherry cultivars and rootstocks in the Northern Lisosteppe of Ukraine

Objects of the researches are 10 cultivars and 4 rootstocks of cherry of the inland and foreign breeding in a nursery and fruit-bearing orchard. Purpose is studying cherry cultivar-rootstock combinations in a nursery and estimating its perspective cultivars biological peculiarities and favourability for cultivation under the conditions of the Ukrainian Northern Lisosteppe. Methods are: field - studying the peculiarities of cherry cultivars growth and productivity in a nursery and orchard, laboratory - determination of the research objects quantitative and qualitative characteristics, mathematical and statistical - estimation of the results probability, calculation- comparative - economic evaluation of growing planting trees in a nursery and cultivars in an orchard. Novelty lies in the fact that for the first time in the Ukrainian Northern Lisosteppe the peculiarities which characterize the level of the grafting components compatibility were detected as a results of the complex physiological research ofcherry cultivar-rootstock combinations. Combinations were selected which being used for duches will ensure the establishment of early-ripening and high-productive orchards. The author studied the biological peculiarities of perspective cherry cultivars of the inland and foreign breeding and carried out the integral estimation of them according to the complex of economic and biological properties. The active temperatures (above 10оС) amount was established for this crop cultivars phonological phases. Anatomical and morphological changes in cherry generative buds were determined in order to substantiate the cultivars frost- resistance and productivity. The dissertant investigated this crop growth and fruit bearing in the Ukrainian Northern Lisosteppe. The best cultivars were singled out which ensured the sufficient profitableness level in the conditions of the market economy. Theoretical and practical results are as follows: the author studied peculiarities of the cherry cultivar-rootstock combinations growth in a nursery, estimated the vegetative rootstocks VSL-2, L-2 and PN favourability for 10 promise cherry cultivars as compared to the mahaleb cherry seedlings, determined objective laws of cherry cultivars growth and development, their attitude to unfavourable environment factors, selected the best pollinators and recommended perspective cultivars for the introduction into production. This makes it possible to increase the orchards average yield by 30-35 % and obtain the ultra-early production of high taste quality. The usage of the best cultivar-rootstock combinations as well as high-productive and well-adapted cherry cultivars recommended for the Lisosteppe will ensure its fruits stable production of high marketable and taste qualities. The results of the researches are used in the education process and investigation work. The branch is agriculture.