Components of photosynthetic activity of cherry trees in the Right-Bank Forest-Steppe of Ukraine

Abstract

The article presents the results of research on the photosynthetic activity of cherry trees. The aim of the research was to study the morphological, growth and biochemical characteristics of the leaf cover of cherry trees depending on the time of fruit ripening. Observations, analysis and laboratory studies reveal morphological and biochemical features of annual tree growth, total leaf surface and content of green pigments in the leaves which is one of the main indicators of photosynthetic potential of fruit trees. It was established that Dar Mlieva was characterized by the largest total length of annual increments among early ripening varieties, Melitopolʹsʹka krapchasta variety – among medium ripening varieties, and Drogana zhovta variety among late ripening varieties. Aborehenka variety had the largest average length of shoots, and Mirage variety had the smallest length. The number of shoots on the tree and the activity of annual new ramules make the shoot-forming ability. Cherry varieties are divided into groups according to the obtained data: with a high degree of shoot formation – Dar Mlieva, Zoryana, Mirage, Melitopolʹsʹka krapchasta and Drogana zhovta; middle degree – Mliivsky zhovta, Aboriginal, Meotida, Amazon and low degree – varieties Alyonushka, Biryuza, Donetsky uholʹok. Low leaf area of cherry plantations negatively affected the activity of the processes of photosynthesis and productivity of plantations aged 6–8 years and made 14–35 % of the optimal. The content of chlorophyll in the leaves depended largely on the characteristics of the pomological variety, while for the maturity of the fruit, the dependence was not detected. The middle maturity cherry varieties of Mirage and Meotida differed favorably in the content in the leaf of pigments of photosynthesis of carotenoids, chlorophyll a, b, as well as the sum of a + bchlorophylls . The content of these indicators exceeded the indicators of other studied varieties by 25 % on average. Key words: sweet cherry, photosynthesis, total leaf surface, length of annual increments, chlorophyll content.