Effect of boron fertilization on sweet cherry tree yield and fruit quality

The goal of the study was to examine response of sweet cherries (Prunus avium L.) to boron (B) fertilization. The experiment was conducted during 2003-2004 in Central Poland on mature 'Buttner's Red' sweet cherry trees planted on a sandy loam soil with low B availability. Trees were soil-or foliar-fertilized with B. Soil B application was made at a rate of 2 kg ha(-1) at the bud-burst stage. Foliar B sprays were performed: (1) in the spring, at the stage of white bud, beginning of flowering, and petal fall and (2) in the fall, approximately four to five weeks before the natural leaf fall. In each of spring spray treatments, B was applied at a rate of 0.2 kg ha(-1) and in the fall at a rate of 0.8 kg ha(-1). Trees untreated with B served as a control. The results showed that B fertilization had no effect on vigor and yield of sweet cherry trees despite increased concentration of this microelement in flower and leaf tissues. Mean fruit weight, titratable acidity, and fruit sensitivity to cracking also were not influenced by B fertilization. Fruits of B-fertilized trees, regardless of the method of its application, had higher concentrations of soluble solids and anthocyanins than did control plants. It is concluded that under conditions of this experiment, B fertilization can be recommended in sweet cherry culture to improve fruit quality and their appearance.