The effects of different grafting times and methods on cultivar change in hazelnut

Orchard renewal in hazelnut is carried out both for the rehabilitation of old orchards and for changing cultivars . However, aplication of changing cultivar is carried out by grafting in most fruit species. Because, in changing the variety with the grafting, the graft sprouts bears fruit in a short time. However, for this purpose, the appropriate grafting time and method should be determined. This study was carried out to determine the effects of different grafting times and methods on cultivar change in hazelnut. The study was carried out in a 30-year-olds orchard in the Salipazarı district of Samsun in 2021 and 2022. In the study, 'Palaz' cultivar was used as rootstock, 'Çakıldak' and 'Yomrali' cultivars were used as scion. The scion woods were taken in January and kept in cold storage at +2°C until the time of grafting. In the study, graftings were carried out with 3 different methods (wedge, whip, chip budding) in 3 periods starting from April 5 in 2021 and April 16 in 2022. In order to determine the effects of grafting methods and times on graft success and plant growth, graft callusing ratio, graft sprouting ratio, survival ratio, shoot length, diameter of graft shoot, plant length and plant diameter were measured. In the study, there was no statistical difference between grafting times in terms of ratios of graft callusing, graft sprouting and survival of graft sprouts. According to years, the average graft success (sprouting ratio) was determined as 87.9% in the whip grafting, 90.4% in the wedge grafting and 42.5% in the chip budding. Scion shoot development was stronger in 'Yomrali' cultivar than 'Cakildak'. As a result of the research, it has been proven that cultivar change in hazelnut can be done by grafting. For cultivar change in hazelnut, the scion woods should be taken in January, when the buds are at full rest, and the grafting should be done in April or May using wedge or whip grafting methods.