Diamondback moth (DBM), Plutella xylostella (L.), has attained major pest status in Brassica vegetable crops around the world. In many cases, use of synthetic pyrethroid insecticides for control of other pests, such as Pieris rapae (L.), has disrupted natural enemies and selected for insecticide resistance in DBM, changing the pest status of the moth from minor to major. We estimated levels of ...

A field study was conducted from 1991 through 1997 to evaluate the use of pyrethroid and organophosphate (OP) ear tags, alternated yearly, for the control of a pyrethroid resistant horn fly, Haematobia irritans (L.), population in Louisiana. Fly resistance was monitored by weekly fly counts, filter paper bioassays and diagnostic polymerase chain reaction (PCR) assays for the presence of pyrethr...

A cross sectional survey on the prevalence of acute pyrethroid poisoning in cotton farmers was conducted in 1987 and 1988. A total of 3113 pyrethroid spraymen (2230 men (71.6%) and 883 women (28.4%] were interviewed after spraying and followed up for 72 hours. Adverse effects of pyrethroid exposure were found in 834 of them (26.8%) manifested as abnormal facial sensations, dizziness, headache, ...

Alpha-cypermethrin is a synthetic pyrethroid insecticide used to control pests in domestic, industrial and agricultural situations. Adult male guppy fish (Poecilia reticulata standard test species) were selected for the bioassay experiments. The experiments were performed in four series and the 96-h LC50 value was determined for guppies. The acute toxicity experiments were carried out by static...

Effect of the deltamethrin, which is extensively used synthetic pyrethroid, was investigated on the lipase activity of Poecilia reticulata in the present study. One control and five experimental groups were exposed to different concentrations of deltamethrin. Three experiments, including 60 guppies each, were conducted. Titration method was used in order to determine the lipase activity. Lipase...

Voltage-gated sodium channels are the primary target of pyrethroid insecticides. Although it is well known that specific mutations in insect sodium channels confer knockdown resistance (kdr) to pyrethroids, the atomic mechanisms of pyrethroid-sodium channel interactions are not clearly understood. Previously, computer modeling and mutational analysis predicted two pyrethroid receptors, pyrethro...