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Hazelnut is a traditional crop of Georgia, where hazelnut growing is enlarging and export is increasing. Samegrelo is the main hazelnut producing region of the country. Unfortunately, different species of insect and mite pests have been detected in the orchards of this region, which cause quality and yield reduction of this valuable crop. In this paper we present the results of a study carried out in five villages of Samegrelo region where we surveyed the incidence of important pests. The three main pests: ambrosia beetle (Xyleborus dispar), bud mite (Phytoptus avellanae) and hazel long-horned beetle (Oberea linearis) were surveyed. X. dispar was widespread and caused considerable damage to hazelnut orchards in all five villages, while P. avellanae and O. linearis were detected in only three of the surveyed orchards. The mean number of abnormal buds and shoots damaged by these pests was not significantly different among the investigated orchards. The locations, surveying details and amount of damage is presented.

5th International Congress on Hazelnut -- AUG 27-31, 2000 -- CORVALLIS, OR WOS: 000173565900072 Surveys conducted in hazelnut orchards in Samsun province during 1997-1998 showed that the most important and widespread pests were nut weevil (Curculio nucum), ambrosia beetle (Xyleborus dispar), big bud mites (Phytoptus avellanae and Cecidophyopsis vermiformis) and hazel longhorned beetle (Obera linearis). Pest populations varied over the four districts. Nut weevil adults appeared from early May to late June, and population density varied between 1-8 adults/10 "ocak". Carsamba and Salipazari districts had higher populations than the other two districts, and mean nut damage was nearly 14%. Big bud mites were widespread and were found in high populations. Big bud numbers varied from one to 7 per trunk, and Ondokuzmayis district had the highest population. Ambrosia beetle was a very serious problem in the Carsamba and Terme districts. Ambrosia beetle adults were seen in late April and early June. Hazel longhorned beetle produced very serious damage in Carsamba, Terme and Salipazari districts and numbers of injured twigs varied between 5-14 per "ocak". Pentatomid bugs (Hemiptera: Pentatomidae), fall webworm (Hyphantria cunea), filbert aphid (Myzocallis coryli), brown scale (Parthenolecanium corni, P. rufulum) and Gypsonema dealbana were found as secondary pests at varying population densities: Int Soc Hort Sci, Oregon State Univ, Coll Agr Sci, Assoc Oregon Hazelnut Ind

The hazelnut (Corylus avellana L.) agroecosystem includes several groups of harmful and beneficial organisms. This paper lists the mite species that have been recorded on hazelnut in Turkey, based on the collections of the authors as well as bibliographical sources, and gives the distribution and economic importance of each species. Forty-five mite species belonging to 20 families were found. The most common and important pest was Phytoptus avellanae Nal., present as both .gall. and .vagrant. forms. Cecidophyopsis vermiformis (Nal.) was also common in hazelnut orchards but has less economic impact than P. avellanae. Tetranycopsis horridus (Can. &Fanz.) was also important, but only on a local scale. Minor pests, widespread but not important, included Aculus comatus (Nal.), Tegonotus depressus Nal., Coptophylla lamimani (Keifer), Anthocoptes loricatus Nal., Eotetranychus coryli (Reck) and Tetranychus sp. The beneficial mite fauna was also rich, including 23 species of predatory mites, the most common of which was Kampimodromus aberrans (Oud.). Additionally, Czenspinskia transversostriata (Oud.) and Tarsonemus stammeri Schaarschmidt are reported for the first time in Turkey.

4th International Symposium on Hazelnut -- JUL 30-AUG 02, 1996 -- ORDU, TURKEY WOS: 000071757700070 Damage types caused by two forms of Phytoptus avellanae Nal. ("gall" and "vagrant" forms) and Cecidophyopsis vermiformis Nal., all of which are commonly found in the hazelnut cultivars in the Blacksea Region, were investigated by periodic sampling. Our results show that the gall form of P. avellanae feeds exclusively on generative buds and causes formation of big buds; whereas the vagrant form of P. avellanae does not cause big bud formation, but feeds intensively on both vegetative and generative buds, on catkins and on young fruit clusters which eventually fall. On the other hand, C. vermiformis itself does not cause formation of big buds, but feeds in big buds created by P. avellanae, and not all big buds are infested with C. vermiformis, Big buds with only P. ave(lanae inside have been termed "spring big buds". Due to intensive feeding and reproduction by C. vermiformis, infested big buds prematurely open and fall down at the end of summer, thus leading to the formation of "summer big buds". The nymphs and adults migrate to spring big buds after the summer big buds dry and form "winter big buds". In addition, C. vermiformis rarely infests vegetative and generative parts which may fall if infestation becomes too heavy. Int Soc Hort Sci, Working Grp Nuts