Overview of walnut culture in Turkey

Abstract

Turkey is located at the germplasm and centre of origin of walnut. J. regia is the only walnut species commonly found while other walnut species are not seen in nature in Turkey. Walnut populations composed of genetically dispersed and rich genotypes grown from seeds in general are spread in almost all geographical regions throughout Turkey. In the early 1980s, walnut orchards have been established with cultivars selected in Turkey. Walnut usage in Turkish cuisine and furniture industries has made this species more valuable than other species. But the increase in walnut timber export caused thousands of walnut trees to be cut especially between the years 1985 and 2000. Import of walnuts is approximately 60,000 t in Turkey where annually 200,000 t of walnuts are produced. This has increased the attention to walnut growing in recent years. Large walnut orchards have been established with government support in Turkey. Recently, domestic walnut cultivars have been replaced by late leafing foreign walnut cultivars with high lateral bud fruitfulness in newly established walnut orchards. It is estimated that import will be reduced by fruiting of the newly established orchards planted with especially 'Chandler' nursery trees. Besides, 10-million walnut-tree-planting projects in 10 years is a new expansion for Turkish walnut growing in the context of the project by the Ministry of Forest and Water Management. Walnut research has been focused on genetics and breeding, irrigation, fertilization, stress physiology, mechanization, control of disease and pest in Turkey.