Neonicotinoids resistance

P. C. Jepson (Oregon State Univ., USA) discussed the effects of pesticides on natural enemies that play a critical role in 1PM. The factors governing the key processes underlying pesticide impact were analyzed to explore ways of mitigating the side effects on beneficial organisms. R. ffrench-Constant (Univ. of Bath, UK) described that neonicotinoid resistance was conferred by DDT-R gene in Drosophila, and therefore required no fitness cost. Y. Suzuki (NARO, Japan)... 

Nauen R, Vontas J, Kaussmann M, Wolfel K (2013) Pymetrozine is hydroxylated by CYP6CM1, a cytochrome P450 conferring neonicotinoid resistance in Bemisi tabaci. Pest Manag Sci 69 457 61... 

Nauen R., Acetylcholine receptors as sites for developing neonicotinoid insecticides, in Biochemical Sites of insecticide action and resistance, Ishaaya, I., Ed., Berlin Springer-Verlag, 2001, p. 77. 

In a recent study, resistance to the neonicotinoid insecticide, imidacloprid, in the brown plant hopper, Nilaparvata lugens, was found to be due to a point mutation at a conserved position in two nAChR subunits. As a result, it reduced the receptor binding of imidacloprid (Liu et al., 2005). 

Yu and Nguyen (1996) showed that selection of a strain of diamondback moth (Plu-tella xylostella) with permethrin for 21 generations resulted in over 600-fold resistance to permethrin in this strain. The resistant strain was also cross-resistant to all pyrethroids tested, including bifenthrin, fenvalerate, esfenvalerate, A.-cyhalothrin, fluvalinate, and tral-omethrin. However, it remained susceptible to organophosphate, carbamate, cyclodiene, neonicotinoid, avermectin, and microbial insecticides tested. Biochemical studies indicated that pyrethroid resistance observed in this strain was most likely due to decreased target site sensitivity. 

Corbel, V., Duchon, S.. 21aim, M., and Hougand. J.-M. (2004). Dinotefuran A potential neonicotinoid insecticide again.st resistant mosquiioes. / Med. Entomol. 41, 712-717,... 

Understanding the selectivity of neonicotinoids toward insect nAChR is essential for environment protection, human health, and insecticide resistance [7], and also a key issue for the design and structure-relationship of new derivatives. 

Recently, resistance to imidacloprid became a serious problem for crop protection. Comparative studies of other neonicotinoids revealed a high crossresistance to acetamiprid and thiamethoxam against imidacloprid-resistant strains [22]. However, bioassays exhibited that 4a has good activity against imidacloprid-resistant strains of brown planthopper (Table IV), showing very low cross-resistance to imidacloprid, as shown in Table V. 

Neonicotinoids, Bioinformatics, an initio Chemistry, Binding Mode, Nitromethene, Tetrahydro-pyridine, QSAR, Cross-Resistance... 

Target-Site Resistance to Neonicotinoid Insecticides in the Brown Planthopper NUaparvata lugens... 

Neonicotinoid, Insecticide, Resistance, Nicotinic Acetylcholine Receptor, Nilaparvata lugens... 

A nicotinic acetylcholine receptor point mutation (Y151S) conferring insecticide resistance causes reduced agonist potency to a range of neonicotinoids (N. S. Millar, Univ. College London, UK)... 

Furthermore, field simulator studies revealed that spiromesifen 8a is also a valuable tool to control pyriproxyfen resistant whiteflies (Fig. 28.4.3). In particular, the combination with neonicotinoid (chloronicotinyl) insecticides such as imi-dacloprid renders spiromesifen 8a as a new valuable tool in resistance management strategies for whitefly control [12]. 

Neonicotinoids are insecticides acting on insect nAChRs (1). For a long time they are very effective on commercially important Hemipteran pest species such as aphids, whiteflies and planthoppers, but also control Coleopteran and some Lepidopteran pests (/). The biochemical mode of action (MoA) of neonicotinoids has been studied and characterized extensively in the past 10 years. Ail neonicotinoids act selectively as agonists at the insect nAChRs and they are part of a single MoA group as defmed by the Insecticide Resistance Action Committee (IRAC an Expert Conunittee of Crop Life) for resistance management purposes (2). Today the neonicotinoids are ... 

Therefore, handling of resistant management strategies in pest control using neonicotinoid insecticides is essential (4). A conversion of neonicotinoid sub types, so-called precursors, into an active neonicotinoid could have a significant impact on this matter. 

The EU ban on neonicotinoids from December 2013 means that seed dressings containing clothianadin, imidacloprid and thiomethoxam can no longer be used for the control of cabbage stem hea beetle (CSFB) or the peach-potato aphid, a vector of turnip yellows virus. Fohar apphed pyrethroids ate now the only control for CSFB, but resistance is now widespread. 

A number of insecticides are approved for use. Many of these insecticides are not conholhng these aphids due to resistance. Currently there is no resistance to the neonicotinoides. 

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