Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) also known as spotted-wing drosophila (SWD), is a pest native to Southeast Asia. In the last few decades, the pest has expanded its range to affect all major European and American fruit production regions. SWD is a highly adaptive insect that is able to disperse, survive, and flourish under a range of environmental conditions. Infestation by SWD generates both direct and indirect economic impacts through yield losses, shorter shelf life of infested fruit, and increased production costs. Fresh markets, frozen berries, and fruit export programs have been impacted by the pest due to zero tolerance for fruit infestation. As SWD control programs rely heavily on insecticides, exceedance of maximum residue levels (MRLs) has also resulted in crop rejections. The economic impact of SWD has been particularly severe for organic operations, mainly due to the limited availability of effective insecticides. Integrated pest management (IPM) of SWD could significantly reduce chemical inputs but would require substantial changes to horticultural management practices. This review evaluates the most promising methods studied as part of an IPM strategy against SWD across the world. For each of the considered techniques, the effectiveness, impact, sustainability, and stage of development are discussed.

Drosophila suzukii (Matsumura) is a vinegar fly species that originates from Eastern Asia and has spread throughout Europe and the Americas since its initial detection in United States in 2008. Its relatively large, sclerotized, and serrated ovipositor enables the ability to penetrate ripening fruits, providing a protected environment for its egg and larval stages. Because the mechanism of oviposition site selection of D. suzukii is a matter of hypothesis, the aim of the present study was to elucidate behavioral and chemical aspects of short-range ovipositional site selection within the context of D. suzukii reproductive biology. The preference of D. suzukii to lay eggs on artificially pierced, previously infested, or intact fruits was tested. Video recordings and photographic evidence documented the release of an anal secretion over the fruit surface near the oviposition sites. Gas chromatographic analysis revealed the presence of 11 compounds detected only on the skin of egg-infested berries. Electroantennographic experiments with both sexes of D. suzukii highlighted the importance of six volatile compounds: methyl myristate, methyl palmitate, myristic acid, lauric acid, palmitic acid, and palmitoleic acid. Finally, a synthetic blend composed of the six compounds in a ratio similar to that found on the skin of egg-infested berries increased the oviposition rate of conspecific females. Data from our work suggest that the identified volatiles are cues for reproductive site selection. We discuss how these oviposition cues may affect the fitness of D. suzukii. The knowledge gained from this study may accelerate establishment of control strategies based on the interference and disruption of D. suzukii communication during the oviposition processes.

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SummaryIn this study, the resistance of two (Aydın and Urla) populations of T. absoluta against five commonly used insecticides (indoxacarb, spinosad, azadirachtin, chlorantraniliprole and metaflumizone) were determined. Further, the activity of insecticide detoxifying enzymes [gluthation-S-transferase (GST) and esterase (EST)] was also evaluated to confirm the resistance. Aydın population of T. absoluta had higher resistant values 8-fold, 3.79-fold, 6.4-fold and 1.84-fold for indoxacarb, metaflumizone, spinosad and chlorantraniliprole, respectively against all insecticides except azadirachtin compared to the Urla population. It was determined that in comparison with T.absoluta population from Aydın, the Urla population can be more susceptible to other insecticides except azadirachtin. GST enzyme activity was 1.5-fold higher in Aydın than the Urla populations, however, EST enzyme had similar activity in both the populations. The results of study imply that T. absoluta populations from Aydın (Turkey) can be resistant against indoxacarb, metaflumizone, spinosad and chlorantraniliprole. Increased GST enzyme activity in resistant populations confirms this resistance development. Insecticides of plant origin like azadirachtin, for which least insecticide resistance was recorded, may be applied in combination with other methods to effectively control T.absoluta. Keywords: Tuta absoluta, resistance, enzymes, leaf dip ÖzetBu çalışmada T. absoluta'nın iki populasyonunun (Aydın ve Urla) en çok kullanılan 5 insektisite karşı (indoxacarb, spinosad, azadirachtin, chlorantraniliprol ve metaflumizon) direnç durumları tespit edilmiştir. Ayrıca detoksifikasyon enzimlerinin [glutation-S-transferaz (GST) ve esteraz (EST)] aktiviteleri de direnci doğrulamak için saptanmıştır. T.absoluta Aydın populasyonunun azadirachtin hariç diğer insektisitlere karşı (Urla populasyonuna göre) sırasıyla indoxacarb, metaflumizon, spinosad ve chlorantaraniliprol'e karşı 8, 3.79, 6.4 ve 1.84 kat direnç geliştirdiği gözlenmiştir. Aydın populasyonu ile karşılaştırıldığında Urla populasyonunun azadirachtin hariç diğer insektisitlere karşı daha duyarlı olabileceği saptanmıştır. GST enzim aktivitesi Urla populasyonuna göre Aydın populasyonunda 1.5-kat fazla iken, EST enzimi için her iki populasyonda benzer sonuçlar bulunmuştur. Çalışmanın sonuçları, Aydın (Türkiye)'dan alınan bir T. absoluta populasyonunun indoxacarb, metaflumizon, spinosad ve chlorantraniliprol'e karşı dirençli olabileceğine işaret etmektedir. Dirençli populasyondaki artan GST enzim aktivitesi, bu direnç gelişimini doğrulamaktadır. En az insektisit direnci rapor edilmiş olan bitkisel kaynaklı insektisit azadirachtin diğer metodlarla birlikte bu zararlının etkili bir şekilde kontrol edilmesinde uygulanabilir.

The concentration and impact of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)-ethane (DDT) and its metabolites (DDE: 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene) on the environment was expected to decrease after its ban in the mid-1980s. Unfortunately, DDT contamination via its presence as an impurity in dicofol (2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol) has led to a new source of contamination. This is particularly true especially in cotton production in Söke Plain, Turkey, where difocol-based pesticides are being used. The aim of this research was to investigate the extent and source of DDT contamination in cotton soils. Söke Plain soil samples were collected from 0-30, 30-60, and 60-90-cm depth and analyzed by GC/MS/MS. o,p'-DDT and p, p'-DDE were detected at 16.2 % and 17.6 % of the sites in the 0-30-cm depth of soils. In the 30-60 cm, p, p'-DDT (14.9 %), o, p'-DDE (8.1 %) and p, p'-DDE (2.7 %) were found in soil samples, and p, p'-DDT was the most prevalent with 9.5 % of the sampling sites. The dominant source of DDT particularly in the 60-90-cm depth was due to historic use of DDT. The presence of p, p'-DDE, o, p'-DDE and p,p'-DDT in the topsoil was attributed to recent dicofol applications.