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A brief overview is presented of the discovery and development of s-methoprene and some other juvenile hormone mimics. The identification of the natural juvenile hormones is described along with an outline of the part they play in the hormonal control of insect development. The properties and commercial applications of s-methoprene are presented with emphasis on its use in mosquito control and its minimal impact on the environment.

Evidence that amphibian deformities are on the rise has prompted a number of researchers to question a variety of natural and man-made substances, including chemicals such as s-methoprene (trademark Altosid), an insect growth regulator applied to water bodies for mosquito control. Despite conclusions reached by the U.S. Environmental Protection Agency and a considerable body of scientific evidence demonstrating that it is unlikely that s-methoprene or any of its degradation products are causing the high rates of deformities found in Minnesota and other states, concerns persist about potential negative impacts of s-methoprene on nontarget species, specifically anurans. Water analyses in field and laboratory conditions and a comparison of reported Altosid use with reported frog deformities in Minnesota demonstrate that a connection between frog deformities and Altosid use is unlikely. These results indicate that factors other than s-methoprene and its degradation products are contributing to the recent outbreak of frog deformities.

Ethyl (2E, 4Z)-2,4-decadienoate, a pear-derived volatile, is a species-specific, durable, and highly potent attractant to the codling moth (CM), Cydia pomonella (L.), a serious pest of walnuts, apples, and pears worldwide. This kairomone attracts both CM males and virgin and mated females. It is highly attractive to CM in both walnut and apple orchard contexts, but has shown limited effectiveness in a pear orchard context. Rubber septa lures loaded with ethyl (2E, 4Z)-2,4-decadienoate remained attractive for several months under field conditions. At the same low microgram load rates on septa, the combined gender capture of CM in kairomone-baited traps was similar to the capture rate of males in traps baited with codlemone, the major sex pheromone component. The particular attribute of attracting CM females renders this kairomone a novel tool for monitoring population flight and mating-ovipositional status, and potentially a major new weapon for directly controlling CM populations.

Two components of the San Jose scale sex pheromone had previously been identified as 7-methyl-3-methylene-7-octen-1-yl propanoate (I) and (Z)-3,7-dimethyl-2,7-octadien-1-yl propanoate (II). An isomer and various homologs have subsequently been synthesized and tested in a greenhouse bioassay. TheE isomer of II (XI) was found to be attractive to male scales. This compound has now been isolated and identified from airborne extracts of virgin female scales. The composition of the natural pheromone was 48.5%, 46.7%, and 4.8% of I, II, and XI, respectively. In field tests in California and New York, synthetic XI was found to be attractive to male scales alone and in combination with I and II, but there was no obvious increase in trap catch when the synthetic isomers were present in the same ratio as in the natural blend.

(-)-Kaur-16-en-19-oic acid and (-)-kaur-16-en-19-oloxygenated derivatives of (-)-kaurene, stimulated seedlingelongation for the two nonallelic dwarf mutants of maize, d-5 and an-1. Replacement of the exocyclic methylene groupattached to ring D by a keto-, methyl-, hydroxymethyl-, carboxy-, or methylcarboxy group resulted in compounds which were biologically inactive. These kaurene derivatives are structurally related to the gibberellins which produce a similar type of elongation for the d-5 and an-1 mutants.