UKRAINIAN HAZELNUTS: CULTIVARS, AGROTECHNICS, PERSPECTIVES

The hazelnut (Corylus avellana L.) is naturally occurring species that is found throughout the Ukraine. Its cultivars (hazelnuts) have been grown in the Crimea for centuries. Systematic scientific research aimed at breeding new hazelnut cultivars and introducing them into farming production began at the Ukrainian Research Institute of Forestry and Forest Amelioration in the late 1930s under Dr. Fedir A. Pavlenko. The main aim was to breed high-yielding nut breeds for improving forest plantations in steppe conditions. To this end various different crosses were effected between Turkish hazelnuts (Corylus colurna L.) other hazelnuts and filberts. The hybrids obtained were valuable as initial material for further breeding. The “bush-trees” had nut yield capacities as high as 8-18 kg, kernel percentages 43-50%, and kernel fat contents of 62-65%. In the 1950s, the main objective of hazelnut breeding was the creation of cultivars that were hardy to winter and drought conditions and that produced highly marketable nuts. These previously bred forms became the forebears of the Ukraine’s commercial cultivars. Since 1981 12 hazelnut cultivars have been included in the Ukraine’s State Register of Plant Cultivars: ‘Bolgrads'ka novynka’, ‘Borovs'kyi’, ‘Dar Pavlenka’, ‘Klynovydnyi’, ‘Koronchatyi’, ‘Lozivs'kyi sharovydnyi’, ‘Pyrizhok’, ‘Raketnyi’, ‘Sriblyastyi’, ‘Stepovyi 83’, ‘Shedevr’, ‘Shokoladnyi’. Plantations of hazelnut have been established in Kharkivs'ka, Donyetska, Kirovograds'ka and other regions of the Ukraine. According to perennial data, the average yield at the Pershotravneva State Cultivar Trial Station (SCTS) was 7-8 metric centneres per ha (some 2.5 kg nuts per bush), at the Kirovograd SCTS it was 11 centneres per ha (4 kg nuts per bush), and at the Melitopol' SCTS (Zaporizhzhya region) - under irrigation - it was about 30 metric centneres per ha. In the 1970s the main research priorities were to increase yield capacity by applying agrotechnical measures: appropriate selection and use of varieties, appropriate choice of pollinators, formation and nursing for bushes, fertilizing, irrigation, and protecting nut yields from nut weevil (Curculio nucum L.). At the same time, phenological observations and biological studies of flowering and fruiting, vegetative propagation, and hybridization were also carried out. In recent years valuable hybrids have been selected with the traits of Siberian filbert (Corylus heterophylla Fisch. ex Trautv.) and hazelnut fruits; with compact and elongated decorative crowns and with a large number of bunches. Six new forms with a high yield capacity have been created, as well as 5 shortish forms which have provided valuable material for the creation of highly profitable plantations. To provide the population of the Ukraine with its own hazelnut resources and to cover domestic demand it is necessary to create over 50,000 hectares of hazelnut plantations. Another way of further increasing the area under hazelnut cultivation would involve promoting low productivity informal plantations in river valleys and also in orchards requiring redevelopment. For these, and on flat plots with fertile soils under steppe and forest-steppe conditions, it is only possible to use rooted outplants of hazelnut cultivars included in the State Register of Plant Cultivars. Experience shows that until hazelnuts begin to fruit on such plots, (5 years), interrows may be used for intertilled cultivation and the production of some other crops. On industrial plantations the most rational spacing for plants is 6 x 6 m, therefore the use of the interrows for growing crops is an additional advantage. On forest parcels with type C₂ growing conditions it may be possible to combine hazelnut cultivation with that of pine trees for use as Christmas trees. These can also be grown together with a relatively close spacing of pine trees (Ukraine patent No. 6191 and Russia patent No. 2025945). The priority certificate on patent application No.2003108957 credits A.P. Ryabokon and V.Y. Slyusarchuk with the invention of a “Method for joint growth of pine trees and filbert in a fresh leafy subforest” for obtaining planting material, nuts and wood. The area under filbert plantations may be increased with the planting of greenery on recultivated land and in recreational zones where land could be dedicated to leisure uses for the general public.