Determination of graft compatibility of some chestnutcultivars and genotypes with 'bouche de betizac' chestnutcultivar

The most important biotic factors threatening chestnut cultivation are chestnut blight and root rot diseases, gall wasp and ambrosia beetle pests. In order to advice the chestnut cultivars, their yield and nut quality, as well as their resistance to diseases and pests, are important. 'Bouche de Betizac' chestnut cultivar is one of the most popular chestnut cultivars in the world due to its tolerance to chestnut blight and resistance to gall wasp. In order to produce certified grafting plants from this cultivar, cultivar registration has also been carried out in Turkey. However, in order to serial production of 'Bouche de Betizac', the rootstocks having good graft compatibility with this cultivar must be determined. This study was carried out to determine the short-term graft compatibility of some chestnut cultivars and genotypes with the 'Bouche de Betizac' cultivar. Eight chestnut genotypes (A9, A30, A41, A55, A56, 'Ali Nihat','Bouche de Betizac' and 'Maraval') were used as rootstocks in the study. Grafting was done on one-year-old seedling rootstocks of these genotypes in September-2018. The trial orchard was established at a forest area in the village of Kayagüney in the Atakum district of Samsun at the end of 2019. In order to determine the graft compatibility of rootstock candidates for 'Bouche de Betizac' cultivar, survival rate (%), plant height (cm), plant diameter (mm) etc. were determined. In the study, the survival rate of 'Bouche de Betizac' according to rootstock genotypes ranged from 15.5% to 87.8%, plant length 200-290 cm, plant diameter 30.5-48.6 mm, crown volume 0.81-4.84 m3 and crown index 0.29-0.48. As a result of the research, A56 genotype and the 'Maraval' cultivar had better graft compatibility with the 'Bouche de Betizac' chestnut cultivar. Clonal propagation of these rootstocks has been recommended.