Susceptibility to spinosad (Success®/Tracer®) of beet armyworm (Spodoptera exigua) from the southern U.S.A. and Southeast Asia was determined through exposure of third instar larvae to dipped cotton leaves. LC50 values of field populations ranged from 0.6 to 14 μg spinosad/ml. Field populations were 3.0 to 70-fold less susceptible to spinosad than was a susceptible reference population. The lea...

Indoxacarb (DPX-MP062) is a recently introduced oxadiazine insecticide with activity against a wide range of pests, including house flies. It is metabolically decarbomethoxylated to DCJW. Selection of field collected house flies with indoxacarb produced a New York indoxacarb-resistant (NYINDR) strain with >118-fold resistance after three generations. Resistance in NYINDR could be partially over...

The presence of cytochrome P-450 and associated mono-oxygenase activities was examined in brain microsomes from male and female mice. Although the cytochrome P-450 level in male mouse brain was very low as compared with mouse liver, the aminopyrine N-demethylase and morphine N-demethylase specific activities in male mouse brain were much higher than those observed in mouse liver. Ethoxycoumarin...

Female Swiss ICR mice were injected ip with 100 or 300 mg 2-bromoethylamine hydrobromide (BEA)/kg body weight. Male Swiss ICR mice were subjected to water deprivation, or treated with 5% dextrose in water, dimethylsulphoxide, piperonyl butoxide, SKF-525A, sodium phenobarbital, beta-naphthoflavone, probenecid, reserpine, diethyl maleate, buthionine sulphoximine or L-cysteine. Urine collected seq...

Although insecticide resistance is a widespread problem for most insect pests, frequently the assessment of resistance occurs over a limited geographic range. Herein, we report the first widespread survey of insecticide resistance in the USA ever undertaken for the house fly, Musca domestica, a major pest in animal production facilities. The levels of resistance to six different insecticides we...

The insecticidal pyrazole ethiprole, applied at rates of 7.5 and 10.0 ppm either alone or in combination treatments with deltamethrin, piperonyl butoxide, and chlorpyrifos-methyl, was evaluated as a protectant of stored wheat and stored corn. The commodities were treated with six treatment combinations, including an untreated control, and held for 6 mo at 22, 27, or 32 degrees C and 57% RH. Bio...

Elevated cytochrome P450 monooxygenase-based metabolism is associated with carbaryl and methyl parathion resistance in western corn rootworm (Diabrotica virgifera virgifera LeConte) populations in the state of Nebraska. The objectives of this study were to identify potential differences in cytochrome P450 in resistant and susceptible rootworm populations using the model substrate 4-chloro-N-met...

Insects have long been known to excrete toxins via the Malpighian (renal) tubules. In addition, exposure to natural or synthetic toxins is commonly associated with increases in the activity of detoxification enzymes such as the P450 monoxygenases (P450s) and the glutathione-S-transferases (GSTs). We examined the links between mechanisms for detoxification and excretion in adult Drosophila melan...

Field populations of Triatoma infestans Klug were collected during 2002 from four villages in northern Argentina (El Chorro, La Toma, El Sauzal, and Salvador Mazza), after application of deltamethrin and other pyrethroids was ineffective. High levels of resistance to the pyrethroid insecticides deltamethrin, beta-cypermethrin, beta-cyfluthrin, and lambda-cyhalothrin were detected in all of the ...