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Resistance Monitoring (resistance + monitoring)
Selected AbstractsResistance monitoring of aluminum plates to microbiologically influenced corrosion using FFT impedance spectroscopy methodsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 7 2006P. Norouzi Abstract It is well know that formation of a passive oxide film on aluminum can enhance its corrosion resistance. However, microbiologically species are able to damage this film. Microbial adhesion is widely accepted as important stage prior to the induction or initiation of biocorrosion. Pseudomonas aeruginosa and Cladosprioum sp. have been commonly associated with the microbiologically influenced corrosion (MIC) of aluminum and its alloys. In this study, the effect of an organic dye (Quinizarin), on the resistance of aluminum plates to MIC has been investigated by some corrosion monitoring methods such as FFT impedance spectroscopy, cyclic voltammetry and SEM (scanning electron microscopy). In this work, the surface of aluminum plates were changed after exposing them (five types: only polished, anodized, anodized and colored, anodized and colored and sealed) to Pseudomonas aeuroginosa in ASW (artificial sea water) as a microbial culture. The results showed that, the mentioned color caused a decrease in the growth of bacteria, because the color acts a protected layer on the surface of aluminum. This characteristic can reduce intensity of biocorrosion on aluminum plates, so the anodized and colored and sealed plates have the most resistance to MIC, and it can be shown and proven by these techniques which are mentioned above. [source] Resistance of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), larvae in Michigan to insecticides with different modes of action and the impact on field residual activityPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 9 2008David Mota-Sanchez Abstract BACKGROUND: The codling moth is one of the principal pests of apple in the world. Resistance monitoring is crucial to the effective management of resistance in codling moth. Three populations of codling moth in neonate larvae were evaluated for resistance to seven insecticides via diet bioassays, and compared with a susceptible population. In addition, apple plots were treated with labeled field rate doses of four insecticides. Treated fruit were exposed to neonate larvae of two populations from commercial orchards. RESULTS: Two populations of codling moth expressed two- and fivefold resistance to azinphos-methyl, seven- and eightfold resistance to phosmet, six- and tenfold resistance to lambda-cyhalothrin, 14- and 16-fold resistance to methoxyfenozide and sixfold resistance to indoxacarb, but no resistance to acetamiprid and spinosad. The impact of the resistance to azinphos-methyl, measured as fruit damage, increased as the insecticide residues aged in the field. In contrast, fruit damage in methoxyfenozide- and lambda-cyhalothrin-treated fruit was observed earlier for resistant codling moth. No differences in efficacy were found for acetamiprid. CONCLUSIONS: Broad-spectrum insecticide resistance was detected for codling moth. Resistance to azinphos-methyl, lambda-cyhalothrin and methoxyfenozide was associated with reduced residual activity in the field. Broad-spectrum resistance presents serious problems for management of the codling moth in Michigan. Copyright © 2008 Society of Chemical Industry [source] Biotypes B and Q of Bemisia tabaci and their relevance to neonicotinoid and pyriproxyfen resistance ,ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 4 2005A. Rami Horowitz Abstract Resistance monitoring for Bemisia tabaci field populations to the juvenile hormone mimic, pyriproxyfen, was conducted from 1996 to 2003 in commercial cotton fields in two areas of Israel: the Ayalon Valley (central Israel) and the Carmel Coast (northwestern Israel). Although the use of pyriproxyfen ceased in these areas in 1996,1997 (because of the resistance), resistance levels to pyriproxyfen declined to some extent in the fields but remained quite stable, and the susceptibility has not been totally restored. Two strains of B. tabaci collected from the Ayalon Valley in the late 1999 and 2002 cotton seasons (AV99L, AV02L) were assayed for their susceptibility to pyriproxyfen at F1, and subsequently a line of each strain was kept under controlled conditions without exposure to insecticides. After maintenance of more than 20 generations under laboratory conditions, the resistance to pyriproxyfen in the untreated strains substantially declined. This decline was concurrent with a replacement of Q biotype by B-type under non-insecticidal regimes; apparently B biotype was more competitive than the pyriproxyfen-resistant Q-type. Selection under controlled conditions with neonicotinoids on these B. tabaci strains resulted in continued pyriproxyfen resistance, predominantly of Q biotype. Based on our data, applications of either pyriproxyfen or neonicotinoids may select for biotype Q, which would survive to a greater degree where these insecticides are applied. Arch. Insect Biochem. Physiol. 58:216,225, 2005. © 2005 Wiley-Liss, Inc. [source] Problems of resistance development in arthropod pests of agricultural crops in RussiaEPPO BULLETIN, Issue 1 2008G. I. Sukhoruchenko This paper presents the results of long-term monitoring of insecticide resistance in populations of agricultural pests in Russia. Over the last 45 years, resistance developments were recorded for 36 arthropod pest species in 11 agricultural crops and pastures in relation to nearly all commonly used plant protection products. Development of group, cross and multiple resistance has been revealed in populations of many economically important pests. Toxicological and phenotypical (for Colorado potato beetle) methods have been devised to monitor the development of pesticide resistance. Based on experience over the last century, systems aimed at preventing the development of pest resistance to insecticides and acaricides are elaborated. These systems are based on resistance monitoring and using plant protection measures which minimize the toxic pressure on agroecosystems. [source] New methods for the detection of insecticide resistant Myzus persicae in the U.K. suction trap networkAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2008James A. Anstead Abstract 1,Myzus persicae is a highly polyphagous pest of U.K. agriculture. It presents particular control difficulties because it has developed resistance to several insecticide classes. 2,For almost 20 years, M. persicae collected in the U.K. suction trap network have been analysed for insecticide resistance and the data disseminated to growers via a resistance bulletin. These data are generated by the biochemical analysis of individuals for two major resistance phenotypes: (i) elevated carboxylesterase and (ii) modified acetylcholinesterase (MACE). 3,The development of new polymerase chain reaction (PCR)-based technologies using fluorescently labelled probes has allowed other resistance mechanisms, such as knockdown resistance to pyrethroids (kdr/super-kdr), to be detected and has greatly increased the speed and accuracy of resistance monitoring. Unfortunately, these newer PCR-based assays are incompatible with the older biochemical assays. 4,The present study describes the development and testing of new compatible methods for detecting elevated carboxylesterases and MACE for use on M. persicae caught in the field or suction traps. 5,These new tests have significant advantages over present methodologies by allowing individual aphids to be tested for three resistance mechanisms quickly and accurately on a single platform. [source] PCR detection of pirimicarb resistance in Australian field isolates of Aphis gossypii Glover (Aphididae: Hemiptera)AUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 1 2009Martin O McLoon Abstract Aphis gossypii Glover (cotton aphid) is a major secondary pest of Australian cotton that readily develops resistance to the carbamate insecticide pirimicarb (Pirimor®) and to organophosphates generally. To test the pirimicarb resistance status of Australian strains of A. gossypii, a polymerase chain reaction (PCR) assay followed by restriction enzyme assay (REA) was designed to identify the AceI polymorphism S431F known to be responsible for resistance. The method was tested against reference and 33 field strains collected over two consecutive seasons. Both methods confirmed pirimicarb resistance in two field strains, one from each cotton season, giving credence to the molecular technique described. The PCR assay proved specific for the AceI gene. This PCR REA assay has the potential to replace bioassay for the routine pirimicarb resistance monitoring in A. gossypii. With the molecular assay providing results in 48 h, compared with 4,8 weeks for bioassay, such an assay could be used before insecticide control. [source] Monitoring insecticide resistance in Australian Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) detects fipronil and spinosad resistanceAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 3 2005Grant A Herron Abstract, Insecticide resistance monitoring using a Potter precision spray tower with discriminating concentration and log dose probability techniques underpins the Australian insecticide management strategy for Frankliniella occidentalis Pergande. Abamectin, acephate, chlorpyrifos, dichlorvos, dimethoate, endosulfan, fipronil, malathion, methamidophos methidathion, methiocarb, methomyl, pyrazophos and spinosad are recommended for use against F. occidentalis but abamectin, methiocarb and pyrazophos are the only chemicals where insecticide resistance has not been detected. Although not registered, chlorfenapyr was effective against F. occidentalis and should be pursued for that purpose. In contrast, chlorpyrifos, dichlorvos and malathion resistance were detected at low to moderate levels throughout the study period putting their sustainable use for F. occidentalis control in doubt. Although it appears that acephate, dimethoate, endosulfan, fipronil, methamidophos, methidathion and spinosad remain effective, some populations contained a small percentage of thrips that survived exposure to a concentration that killed 100% of the susceptible strain. Subsequent laboratory selection of one such population separately with fipronil and spinosad caused an increase in resistance to these insecticides. These products must now be considered at risk. This is the first report of fipronil or spinosad resistance in populations of F. occidentalis. [source] | |||||||||||||