(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Metazoa: NE > Eumetazoa: NE > Bilateria: NE > Protostomia: NE > Ecdysozoa: NE > Panarthropoda: NE > Arthropoda: NE > Mandibulata: NE > Pancrustacea: NE > Hexapoda: NE > Insecta: NE > Dicondylia: NE > Pterygota: NE > Neoptera: NE > Holometabola: NE > Amphiesmenoptera: NE > Lepidoptera: NE > Glossata: NE > Neolepidoptera: NE > Heteroneura: NE > Ditrysia: NE > Gelechioidea: NE > Gelechiidae: NE > Gelechiinae: NE > Tuta: NE > Tuta absoluta: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA ELDTILPRIEDHETSSKRSKIEDETSSKRVKFDTYYSNHERAEEVLMADD PNLGPEEDDPLVVRTRKGRVRGITLTAVTGKKVDAWFGIPYAQKPIGDLR FRHPRPTEGWGEEILNTTTLPHSCVQIIDNVFGDFPGAMMWNPNTDMQED CLYINIVVPKPRPKNAAVMLWVFGGGFYSGTATLDVYDPKILVSEEKVVY VSMQYRVASLGFLFFDTPDVPGNAGLFDQLMALQWVKDNIAYFGGNPHNV TLFGESSGAASVSLHLLSPLSRNYFSQAIMQSGAATLPWAIISREESILR GIRLAEAVHCPYSRNDVGPMIECLRKKTPEELVNNEWGTLGICEFPFVPI IDGSFLDEMPARSLAHQNFKKTNLLMGSNTEEGYYFILYYLTEMMPKEEN VGISREQYLQAVKELNPYVNDIVRQAIVYEYTDWLNPNDPVKNRNALDKM VGDYHFTCSVNEFAHRYAETGNNVYTYYYKHRSKNNPWPSWTGVLHADEI NYVFGEPLNPGKNYSPEEVEFSKRIMRYWSNFARTGNPSMNPNGELTNPV WPLHSPLGREYLALGVNESSVGQGVRVKECAFWQKYLPQLIAATSKPDPP KNCTSSA
BACKGROUND: Tuta absoluta is a devastating pest in tomato production areas worldwide. After its first introduction to Turkey in 2009, it quickly became the major pest of tomato growing areas. Although some biocontrol agents have been used especially in greenhouses, the main control of T. absoluta relies heavily on chemical insecticides. However, failure in chemical control has often been reported due to resistance development. In this study, we investigated: 1) the population structure of 22 T. absoluta populations across Turkey, by analysing haplotypes, based on the cytochrome oxidase subunit I gene; 2) the efficacy of three registered insecticides from different classes (metaflumizone, chlorantraniliprole and spinosad) in real field - greenhouse conditions; 3) the geographic distribution of target-site mutations associated with insecticide resistance. RESULTS: The efficacy of spinosad was higher than chlorantraniliprole and metaflumizone in the greenhouse trials, as documented by the mortality rates obtained, up to 14 days post application. Known resistance mutations in ryanodine receptors (RyR) (i.e. the I4790M/K and G4946E), nicotinic acetylcholine receptors (G275E), acetylcholinesterases (A201S) and voltage-gated sodium channels (F1845Y and V1848I) were found at various frequencies, across the populations genotyped. The I4790K diamide resistance mutation in the RyR has been reported for the first time in T. absoluta populations. Although a total of 8 haplotypes were found, the overall mean genetic distance was lower than 0.001 indicating the high genetic homogeneity among Turkish T. absoluta populations. CONCLUSION: The results will contribute to design area-wide resistance management programs in T. absoluta control in Turkey. However, more monitoring studies are needed to implement evidence-based IRM strategies in the frame of integrated pest management (IPM). This article is protected by copyright. All rights reserved.
The tomato leaf miner, Tuta absoluta (Lepidoptera: Gelechiidae), is a major invasive pest that has spread throughout many countries in the Mediterranean basin and parts of Asia over the last decade. The control of T. absoluta has relied heavily on the use of chemical insecticides, a strategy that has led to the evolution of resistance. In this study, biological and molecular methods were used to determine the susceptibility of five strains of T. absoluta to the organophosphate chlorpyrifos and to investigate the molecular mechanisms underlying resistance to this class of insecticides. High levels of resistance to chlorpyrifos were observed in all five strains tested. Cloning and sequencing of the gene encoding the organophosphate target site, ace-1, of T. absoluta revealed the presence of an alanine to serine substitution at a position that has been previously linked with organophosphate resistance across a range of different insect and mite species. The presence of this mutation at high frequency in T. absoluta populations originating from various countries further supports the suggestion that the rapid expansion of this species is, in part, mediated by the resistance of this pest to chemical insecticides.
