Insect development disrupters

An Example from Insect Development Disrupter fIDD> Discovery... 

Figure 3 A ballast position in an insect development disrupter.

In principle, the practical application of the ecdysones and ecdysoids known so far should be made possible by their property of disrupting insect development or reproduction when applied in sufficiently high dosages. However, their use is impeded by the high cost of their preparation. 

Dhadialla, T.S., Retnakaran, A., Smagghe, G., 1998, Insect growth-and development-disrupting insecticides in Comprehensive Insect Molecular Science, Vol. 6, Gilbert, L.l., latrou, K., Gill, S.S. (Eds) Elsevier Pergamon, New York, 55-100. 

Many pesticides cause endocrine disruption in vertebrate and invertebrate species at concentrations that are not overtly metabolically toxic. The insect growth inhibitor diflubenzuron can affect the reproduction, development and behaviour of estuarine crustaceans at concentrations of just lOmgP (reviewed... 

It also might interfere with the rate of plant development, thereby disrupting the normal life cycle of insect pests. This, in turn, may offer a new method of insect control. 

These compounds vary, from the natural product rotenone (from Derris or Lonchocarpus root, used to control vegetable and fruit insects) to the synthetics sulfluramid and hydramethylnon (used to control mites and cockroaches). Interestingly, the highest acute toxicity to mammals is caused by the natural product rotenone. These compounds affect the production of adenosine triphosphate (ATP), the energy storage molecule of the cell that is produced by mitochondria, the powerhouse of the cell. The disruption of energy metabolism and the subsequent loss of ATP result in a slowly developing toxicity, and the effects of all these compounds include inactivity, paralysis, and death. 

The most intensive effort to use pheromones in insect management has been in Australia, where an attract-and-kill strategy has been developed for protecting stone fruit crops. Historically, the Oriental fruit moth, Grapholita molesta Busck, was the major stone fruit pest, and heavy insecticide applications kept both this moth and, coincidentally, the Carpophilus beetles at acceptable levels. However, the widespread adoption of pheromone-based mating disruption for G. molesta control released the Carpophilus beetles from insecticide pressure, and these beetles, Ca. davidsoni in particular, became the dominant stone fruit pests (James et al., 1994). Late applications of broad-spectrum insecticides often... 

Although pheromone traps are now widely used for monitoring insect populations, the use of synthetic pheromones in control of insect pests by disruption of pheromone-mediated communication has been much slower to develop, at least in part because of the difficulties of formulation. There are three main types of formulation currently available - hollow fibres, plastic laminates and microcapsules. For several years, the UK Overseas... 

Development Administration and ICI Ltd. have been involved In a collaborative project to develop microencapsulated formulations of lepidopterous sex pheromones for control of insect pests by mating disruption. 

---