Effect of tree pruning intensity on the yield and fruit quality of the sour cherry

The aim of the study was to estimate the effect of' tree pruning intensity on the yielding and quality of fruits of the sour cherry (Prunus cerasus L.) cultivar 'Lutowka'. An experiment with a different intensity of tree pruning was carried out in the years 2006-2010. The study material consisted of one-year old budded plants of the first class: cv. 'Lutowka' type IR2, on Prunus mahaleb rootstock, planted in the spring of 2001 and 2002 spaced 4.0 x 1.3 m giving a total of 1920 trees ha(-1). In the plantation, three pruning regimes were applied: 1) no pruning (only sanitation felling was applied), 2) moderate traditional pruning (consisting of the shortening of branches), 3) intensive pruning (by removing branches older than three years). Tree yielding significantly depended on the weather conditions of the experimental years. With increasing pruning intensity the yield decreased. Tree pruning and its intensity influenced fruit quality measured by the weight of 100 fruits, fruit firmness, acidity and total soluble solids. Colour variation of 'Lutowka' skin was assigned the following parameters L*, a*, b*, C* and h degrees. Their changes varied depending on the year and orchard.