Use of chinese hazel (Corylus chinese French.) in hazelnut breeding (Corylus domestica Kos. st Opal.)

Abstract

Aim. The need to improve the domestic assortment of hazelnuts and encouraging results obtained due to the involvement of Chinese hazel Corylus chinensis Franch. in hybridization with the best of its cultivars, prompted the research. Methods. The hybridization program included the most adapted to the conditions of Ukraine domestic and foreign cultivars of hazelnuts, as well as pollinators from natural populations of Corylus avellana L. and Corylus chinensis. Isolation of maternal and collection of pollen from paternal components of crossing was made using standard methods. Pollination was made by blowing pollen into bags with a medical insufflator MO-03 with a special needle (without removing the bag) and after 2–3 days, the pollination was repeated. Hybrid nuts were sown in autumn with wrappers without stratification. Other operations for growing seedlings and further maintenance were performed according to the standard methods. Results. Sufficiently high levels of fruit binding in variants with C. avellana pollen confirm the genetic proximity of the studied cultivars to this species, and the indicators from pollination by C. chinensis were 3–5 times lower. They confirm the remoteness of Chinese hazel from the modern cultivar assortment, but they make it possible to use this species in the hazelnut breeding. Thanks to this, a valuable material was created from which a new cultivar Sofiyvsky 15 was selected. It entered fruiting in the third year after crossing and combines high potential productivity with adaptability, a spherical shape of the fruit and a high content of raw protein and oil in them. Conclusions. The ‘Sofiyivsky 15’ has significantly exceeded the ‘Halle’ and the conditional standard due to its adaptability, quickness, processability and quality of nuts. It can be recommended for wide introduction in farms of all agro-climatic zones of Ukraine. Keywords: Corylus chinensis Franch., Corylus spp., cultivar Sofiyivsky 15, hazelnut hybrids, hybrid orchard, interspecific crossing.