Hazelnut Pests of Silkroad Countries, with Specific Emphasis on Pests of Georgia

Abstract

Hazelnut is a very important crop for some silkroad countries such as Turkey, Georgia and Azerbaijan. Insect and mite pests are major detriments to hazelnut production. More than several hundreds of insect and mite species have been found in hazelnut orchards up to today. About 10 insect and mite species are serious pests for hazelnut production, with changes among countries. These pests affect the yield and kernel quality as well as the health of trees. Nearly more than 20% losses are caused by hazelnut pests in orchards, with changes in countries and years. Hazelnut is a traditional crop of Georgia and hazelnut growing is enlarging over the past few years in this country. In the current paper, two main topics are considered about hazelnut pests: 1) important hazelnut pests of silkroad countries and their management, 2) current situation of hazelnut pests of Georgia, depending on the results of large scale survey carried out in Georgian hazelnut orchards in 2013. The survey was performed in four main hazelnut growing area, including Ajara, Guria, Samegrelo and Gali, with visiting various towns of each main district on each surveying date. Four main insect and mite pests including Hyphantria cunea, Curculio nucum, Phytoptus avellana and Obera linearis were selected and surveyed, depending on previous data and observations made in previous years. As a general result; H. cunea was very common in all regions in spite of lower population level compared to previous years. C. nucum damage ratio was very high in some parts of Guria especially with some local cultivars. P. avellana was very widespread in all surveyed districts, with reaching very high populations in some towns of Guria. High population of O. linearis was observed in the Gali district. All results according to pests, locations, surveying and sampling dates were given in this study with details.