Optimization of Urea Fertilization with Various Doses and Applications on the Yield and Quality of the Hazelnut

Nitrogen (N) fertilization is one of the necessary elements in the production of hazelnuts. Therefore, the excessive introduction of nitrogen into the soil at once, in order to satisfy this requirement, causes it to leach easily from the soil. The aim of this research was to ensure that nitrogen fertilization applied to hazelnut production is washed off the soil to a minimum level. It was also a matter of developing methods to obtain the highest yield with optimal N fertilization in order to provide a high level of availability to the plant. For this reason, the urea fertilizer was studied with two applications and methods. According to the results of the research, it was concluded that the subsurface application of urea fertilizer at the rate of 50% twice enhanced the effect on the quantitative and qualitative properties of hazelnut. As a result, protein levels, kernel ratio, nutrients concentration in the leaf and yield in hazelnut statistically increased.