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Hazelnut is one of the leading agricultural crops in Georgia. It is cultivated on 8% of the arable area in Georgia and is of great economic importance. Therefore, it is important to protect hazelnut plants from pests in order to produce high quality nuts and minimize losses. In recent years, the ‘big bud mites’ have become major pests of hazelnut plantations in Georgia. Their timely detection and diagnostics will enable the implementation of effective control measures. For this study, 20 orchards in the western Georgia regions of Guria, Samegrelo and Adjara were selected. The species identification and phylogenetic analysis were carried through the sequencing of PCR fragments. The comparison of sequence results to reference isolates of Phytoptus avellanae in Genbank showed high percentage similarity (93-99%). Phylogenetic analysis were conducted in MEGA7 by using UPGMA methods. The phylogenetic trees show that Georgian isolates are grouped in two main clades. First clade contains 15 Georgian and 3 GenBank (KR149013.1, KR149017.1, KT070248.1) isolates of P. avellanae. Microhabitat of all these isolates were buds. The second clade contains 6 Georgian isolates and two isolates from GenBank (KR149026.1 and KR149027.1.), which were isolated from vagrant forms of P. avellanae. The phylogenetic trees show that Georgian isolate GUR1 is separate from Genbank and Georgian isolates. © 2018 Bull. Georg. Natl. Acad. Sci. Shota Rustaveli National Science Foundation: YS-2016-53 This work was supported by a Shota Rustaveli National Science Foundation (SRNSF) project (YS-2016-53) “Detection of hazelnut harmful mite –Phytoptus avellanae and Cecidophyopsis vermiformis – in hazelnut species common to the West Georgia Regions”. We sincerely thanks Ketevan Badalashvili (Laboratory of the Ministry of Agriculture (LMA), Tbilisi, Georgia), Prof. Medea Burdjanadze (Agricultural University of Georgia, V. Gulisashvili Institute of Forestry, Tbilisi, Georgia) and Manana Mindadze (The Ministry of Environmental Protection and Agriculture of Georgia) for collecting samples in the West Georgia.

6th International Congress on Hazelnut -- JUN 14-18, 2004 -- Tarragona Reus, SPAIN Ozman-Sullivan, Sebahat/0000-0001-5240-8110 WOS: 000233635700054 The big bud mites Phytoptus avellanae Nal. and Cecidophyopsis vermifomis Nal. cause significant yield loss in hazelnut (Corylus avellana L.) orchards. Determination of effective pesticides and the proper timing of their application against big bud mites were studied in the Samsun province of Turkey. Two field trials were conducted from 1994 to 1997. The migration period of the mites (April-May) was covered each year. Nine pesticides (Sulphur WP, Azinphos-methyl EC, Azinphos-methyl WP, Dimethoate EC, Bromopropylate EC, Amitraz EC, Quinomethionate WP, Carbosulfan EC and Methidathion EC) were evaluated at their registered application rates as alternatives to the standard pesticide Endosulfan EC. Sulphur 80% WP was as effective (83.25%) as Endosulfan 35% EC (83.35%) for the control of big bud mites. A single application of Sulphur 80% WP (400 g/100 L) at the end of April or beginning of May, just before the peak period of mite migration from old big buds to new buds, was very effective in keeping mite and big bud numbers low.

5th International Congress on Hazelnut -- AUG 27-31, 2000 -- CORVALLIS, OR WOS: 000173565900063 Insect and mite pests are serious problems in Turkish hazelnut orchards and constitute a major impediment to hazelnut production. Although there are hundreds of pest species, only ten of them are common and cause economic damage. The amount of damage varies over regions and years. In addition to pest species, almost 130 natural enemy species have been found. Most growers use chemicals to control pests, and the number of applications ranges from one to four. This causes a decrease in the effectiveness of natural enemies, an increase in environmental contamination and other well-known problems. On the other hand, some farmers use neither chemicals nor other pest-control measures, and some pests have become more serious in recent years. In this paper, the development and improvement of Integrated Pest Management programs for Turkish hazelnut orchards are discussed. Int Soc Hort Sci, Oregon State Univ, Coll Agr Sci, Assoc Oregon Hazelnut Ind

4th International Symposium on Hazelnut -- JUL 30-AUG 02, 1996 -- ORDU, TURKEY Ozman-Sullivan, Sebahat/0000-0001-5240-8110 WOS: 000071757700065 During 1992-1994 we have investigated in detail the life cycles of the two forms of Phytoptus avellanae Nal. ("gall" and "vagrant" forms) and of Cecidophyopsis vermifomris Nal. which cause serious worldwide damage in hazelnut cultivars. Selected hazelnut plantations from the Blacksea Region of Turkey were visited every 2-3 days during the migration period, once every two weeks during the winter months and weekly for the rest of the year and samples were collected. The gall form of P. avellanae has a single nymph form and a simple life cycle. In spring, nymphs migrate from old big buds to healthy buds where feeding and reproduction continues until the following spring. Since the entire population is stationary within the same bud throughout the year, generations overlap. The vagrant form of P. avellanae has a different and rather complex life cycle and two forms of nymphs are present. The vagrant form feeds not only on big buds but also on vegetative and generative parts such as leaves, male and female flowers and completes its life cycle even in the absence of big buds. C. vermiformis also has a complex life cycle with two migration periods in spring and autumn. It lives inside the big buds created by P. avellanae and its generations overlap. C. vermiformis is rarely found on male and female flowers and vegetative buds. Int Soc Hort Sci, Working Grp Nuts

4th International Symposium on Hazelnut -- JUL 30-AUG 02, 1996 -- ORDU, TURKEY Ozman-Sullivan, Sebahat/0000-0001-5240-8110 WOS: 000071757700067 Phytoptus avellanae Nal. and Cecidophyopsis vermifomris Nal. commonly infest hazelnut plantations in the Blacksea Region. This study was performed on Tombul and Uzunmusa cultivars with periodic sampling during 1992-1994, in Samsun. Population fluctuations of the two species were investigated on big buds which contained either eggs, nymphs, adults of both species together or P. avellanae only. Although the numbers of P. avellanae in newly infested buds are very low in early summer, they reach maximum population levels during the following spring. C. vermiformis inside the summer big buds reaches the maximum population level in early autumn while C. vermiformis inside the winter big buds reaches the maximum population level in spring. In summer big buds infested by both species, the two populations are approximately equal in early summer whereas C. vermiformis becomes the dominant species from the end of July onwards. In winter big buds, although the number of C. vermiformis entering the big buds is low in autumn, C. vermiformis is usually the predominant population in spring. Int Soc Hort Sci, Working Grp Nuts