Effect of colemanite boron fertilization on hazelnut (Corylus avellanaL.) yield and nutrient concentration of leaf

In this research, the effect of boron fertilization on leaf mineral concentration, nut yield and percent kernel in 'Tombul' hazelnut was determined. The experiment in a randomized complete block design was carried out in a farm orchard with soil B concentration of 0.02 mg kg(-1) in Carsamba-Samsun location in 2013 and 2014 using boron fertilizer of colemanite source. Boron fertilization was carried out as 6 g B ocak(-1) (T(1)) and 12 g B ocak(-1) (T2), along with the control (T(0)). Supplying doses of colemanite (T(1) and T(2)) resulted in an increase in nut yield in both years, in comparison to the control. The yield increase due to boron application in the first year was statistically nonsignificant. In the second year, boron fertilization caused a significant yield increase from 55.5 kg da(-1) in the control plot to 69.2 and 72.4 kg da(-1) in T(1) and T(2) applications, with a 24.7 and 30.4% yield increase, respectively. As a result of increasing doses (T(1) and T(2)) of B fertilization of colemanite source, increases in nut yield were determined. 6 g B ocak(-1) soil colemanite application produced significant yield increases in both years as compared to the control and percent kernel, these increased from 48 to 52%, and from 46 to 50% in the first and second year with 8.3 and 8.6% increases, respectively. In hazelnut orchards with boron deficiency, boron fertilization increased the cluster formation, nut yield and percent kernel, decreasing empty hazelnuts.