Insect growth regulators, development

Stable in acidic, neutral and basic aqueous solutions Pale yellowish solid, faint characteristic odor Flash point 119°C (Pensky-Martens closed tester) Pyriproxyfen is an insect growth regulator which acts both as an ovacide and as an inhibitor of development (juvenile hormone mimic) against white flies, scale, and psylla. The specificity of pyriproxyfen, and its low mammalian toxicity, allow for some variation in application timing. For example, the lack of toxicity to bees allows pyriproxyfen to be applied during bloom on apple trees, and its low mammalian toxicity allows for a very short pre-harvest interval on citrus The residue definition is for pyriproxyfen alone... 

An aerosol formulation of the insect growth regulator hydroprene (Gen-trol) was labeled several years ago for use in the United States. There are no research reports with hydroprene aerosol, except for Bell and Edwards (1998), which describe a study conducted in Great Britain. In this study, aerosol applications of hydroprene (Protrol) prevented the development of eggs of the red flour beetle, T. castaneum, the confused flour beetle, T. confusum, and the almond moth, C. cautella, that had been placed in exposed dishes with food media. 

The presence of a sensitive life stage or period may also be one of the causes of latency. For example, the effects of diflubenzuron (an insect growth regulator) on aquatic macroinvertebrates were not observed until molting began, some 2 to 4 weeks after a single exposure (Hurd et al. 1996). When larvae of the trichopteran Limnephilus lunatus were exposed for 1 hour to 0.1 pg/L fenvalerate, and subsequently placed in contaminant-free artificial streams, there were few mortalities, but a delay in development and emergence was observed (Liess and Schulz 1996). In aquatic ecosystems that periodically dry out in summer, such a delay in development time may have severe consequences for population survival (Liess 1998). 

The multiresistant strains now extant also show a certain cross-tolerance, but not resistance, to the third-generation insecticides such as the juvenile-hormone mimics and other so-called insect growth regulators, as was found in strains of the housefly, flour beetle and tobacco budworm. Resistance to the JH mimic methoprene and Monsanto-585 has been induced by laboratory selection of Culex taxsalis (28) and Culex pipiens (29), and to Monsanto-585 in Culex quinquefasstatus (30). Whatever insect or IGR is chosen, the result of exposure to selective doses in successive generations is usually the development of resistance, repeating our previous experience with chemosterilants, and the... 

The Control of Insect Growth" symposium, organized by Julius Menn, highlighted recent advances in the biochemistry of regulation of development by insect growth regulators, anti juvenile hormones, and behavior modification governed by antifeedants, pheromones, and defensive secretions. 

In addition to their well established role in catalyzing the metabolism of a wide variety of naturally occurring and synthetic xenobiotics, cytochrome P-450-mediated mixed-function oxidases are of critical Importance in the biosynthesis and regulation of the major hormones (ecdysteroids and juvenile hormone) that control insect growth and development. The characteristics of the mixed-function oxidases involved in the synthesis of insect hormones are described and the possibility that the enzymes might represent potential targets for insect control is discussed. 

Dlflubenzuron. The benzoylphenyl urea Insect growth regulators, for example, pose a formidable residue analysis problem. The compounds are nonvolatile and thus must be derivatized for GC analysis by a rather arduous chemical procedure. The immunoassay developed in this laboratory is much more sensitive and reproducible at a fraction of the cost and can be used to analyze the more difficult matrices such as milk. For instance, a sensitivity of 1 ppb is routinely obtained when milk is added directly to the assay ( .). A series of partition steps can also be added to further clean dlflubenzuron milk extracts yielding a sensitivity in the low ppt range (4). However this increase in sensitivity may not be needed since methods in current use provide a detection limit of only 10-50 ppb. 

CAS 8003-34-7. Any of a group of insect growth regulators that act as neurotoxins, analogous to juvenile hormones, restricting the development of insect larvae. Thus they are especially effective against insects that are destructive in the adult stage. They are considered nontoxic to animals and humans. 

Bengston, M., Koch, K. and Strange, A.C. (1992) Development of insect growth regulators in Australia and South-east Asia. In Proceedings of the 5th International Working Conference on Stored Product Protection, Bordeaux, France, September 1992, Fleurat-Lessard, F. and Ducom, P. pp. 485-490. 

Smagghe, G., Salem, H., Tirry, L. and Degheele, D. (1996) Action of a novel insect growth regulator, tebufenozide against different development stages of four stored product insects. Parasitica 52, 61-69. 

La Clair, J.J., J.A. Bantle, and J. Dumont. 1998. Photoproducts and metabolites of a common insect growth regulator produce development deformities in Xenopus. Environ. Sci. Technol. 32 1453-1461. 

Buprofezin is a specific poison for Homoptera, but the mode of action is not known. It is included in this chapter because it probably interferes with molting or chitin synthesis in some way It inhibits embryogenesis and progeny formation of some insects at very low concentrations (see Ishaaya, 1992). Cyromazil was first marketed in 1980 and is an insect growth regulator. Insect larvae, particularly fly larvae, develop cuticular lesions before they eventually die. 

Thompson HM, Wilkins S, Battersby AH, Waite RJ, Wilkinson D. 2005. The effects of four insect growth-regulating (igr) insecticides on honeybee (Apis mellifera L.) colony development, queen rearing and drone sperm production. Ecotoxicology 14 757-769. 

The first test of an insect growth regulator (IGR) on a non-Apis bee was presented during a symposium in 1993 [25], The authors observed adult mortality and brood development in bumble bee colonies B. ter-restris) maintained in cages. Forage plants were treated during activity hours with the IGR fenoxycarb. It was concluded that the IGR did not present a negative action on adult bumble bees but that a larval test had to be developed for an adequate assessment of the brood mortality. 

Ammar IMA, Darwish ETE, Farag Al, Eisa AA. Detrimental effects of five molt-inhibiting insect growth regulators on the development and reproduction of the cabbage aphid, Brevicoryne brassicae (L.). J. Appl. Entomol. 1986, 102(4), 417-422. 

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