Insecticidal sequestration

Fate and transport modeling was nsed to estimate the concentration of the insecticide in insect tissne consnmed by birds. The details of this modeling effort, which we omit here, are rather complex and involve characteristics of the field application of the insecticide, local weather, mnltiple pathways of exposure to insects, sequestration of insecticide by mortality of insects, and integration over 0- to 20-g pools of insect tissne that wonld compose a bird s daily diet. The model of the pesticide s fate and transport made a prediction abont the concentration variable, which is characterized by the p-box shown in the lower left graph of Figure 6.14. This p-box synthesizes all of the knowledge and nncertainty captured in the modeling effort. The model predicts the distribntion fnnction for concentrations, whatever it is, snrely lies within the bonnds shown. 

Sequestration in insects This is another resistance mechanism in which GSTs were found to be involved in pyrethroid resistance. Kostaropoulos et al. (2001) have reported that GST confers protection against deltamethrin by binding to the insecticide in the yellow mealworm ijenebrio monitor). 

Our current understanding of insecticide resistance phenomena in insects and other arthropods is based upon genetic and biochemical evidence, which implicates a number of different mechanisms (1). These include metabolic mechanisms, which result in enhanced rates of insecticide detoxication or sequestration of insecticide, and also mechanisms involving reduced... 

The chemical defense of plants is observed to act against insects at two different levels as a direct toxin (insecticidal) and as an indirect toxin (antifeedant or growth inhibitor). In a contradictory sense, plant phytochemicals are also involved in another interrelationship with insects ( sequestration) in which the chemical toxins of the plant are utilized by the insect to provide it with a defense against its predators. 

---