Effect of late season boron spray on boron accumulation and fruit set of ‘Summit‘ and ‘Hedelfinger’ sweet cherry (Prunus avium L.)

Abstract

The influence of late-season boron (B) application on the bud B concentration and fruit set was studied in sweet cherry (Prunus avium L.). The experiment was carried out on 5-year-old ‘Summit’ and ‘Hedelfinger’ trees on rootstock Gisela 5 in Fruit Growing centre Gačnik.  Trees were sprayed with B (1% Bortrack) or water (control). Differences in B concentration were measured between cultivars, the highest content in ‘Hedelfinger’ buds. Boron application resulted in increased B concentration in flower buds. Fruit set was influenced with cultivar, boron application and micro location. Fruit set was statistically higher in ‘Hedelfinger’ than in ‘Summit’ trees. The results showed that B fertilization had no effect on fruit set of ‘Summit’ despite increased concentration of boron by 94.8% in dormant flower buds. Foliar boron spraying of ‘Hedelfinger’ was effective in increasing B concentration (by 157.2%) and fruit set on half trees.