Can Juvenile Hormone Research Help Rejuvenate Integrated Pest Management?

Abstract

In the 1960s, the prediction that synthetic juvenile hormones (JHs) and their analogs would form the basis of a new generation of insecticides with enhanced target specificity greatly stimulated research on this hormone. Although JH-based insecticides were found to be effective against certain groups of insect pests, their shortcomings soon became apparent; however, current JH research provides new opportunities and ideas for the development of innovative integrated pest management (IPM) tools and strategies aimed at disrupting JH functions. Interfering with JH endocrinology requires that we either artificially increase JH titers at stages of development when titers are normally low or artificially reduce JH titers at stages of development when titers are normally high. Our discussion is organized around these two conceptual approaches and covers such areas as (i) the isolation and cloning of JH receptors; (ii) the characterization of polydnavirus and entomopoxvirus gene products responsible for the inhibition of host metamorphosis; (iii) the isolation and molecular cloning of allatostatins and the design of allatostatic pseudopeptides; (iv) the characterization of JH biosynthetic enzymes specific to the Lepidoptera; (v) the characterization of regulatory material originating from parasitic wasps of the genus Chelonus Panzer (Hymenoptera: Braconidae), which induce precocious metamorphosis in their hosts; (vi) a tree resistance mechanism involving anti-JH effects resulting in the failure of female insects to produce and lay eggs; and (vii) the cloning of JH esterase and epoxide hydrolase cDNAs and the production of recombinant baculoviruses that overexpress these JH-degradative enzymes.

In vivoeffects ofManduca sextaallatotropin and allatostatin on development and reproduction in the fall armyworm,Spodoptera frugiperda(Lepidoptera, Noctuidae)

“…However, in view of the considerable progress made recently towards development of stable and more lipophilic peptidomimetic analogs, the idea of using neuropeptides as the active principle of biorational insecticides is worth pursuing (Masler et al, 1993;Altstein and Gilon, 2000;Cusson and Palli, 2000). The present paper is meant as an exploratory study with a view to future application of allato-regulating neuropeptides in lepidopteran pest control.…”

“…These processes include the control of ecdysteroid and JH biosyntheses, initiation of behavioural patterns associated with ecdysis, regulation of energy metabolism, etc. Any interference in the homeostasis of these hormones with exogenous sources of the hormones or with synthetic analogs (agonists or antagonists) would result in the disruption or abnormal course of the development and reproduction of the target insects (Dhadialla et al, 1998;Hoffmann and Lorenz, 1998;Cusson and Palli, 2000). Recent advances in.…”

Characterization and tissue‐specific expression of two lepidopteran farnesyl diphosphate synthase homologs: Implications for the biosynthesis of ethyl‐substituted juvenile hormones

“…For the present study, we wanted to evaluate the hypothesis that the Lepidoptera, which produce FPP and homologous FPP structures, do so by the involvement of more than one FPPS, as suggested by earlier work on B. mori. 12, 13 We were also interested in exploring the possibility that one of these proteins displays unique active site features that could confer a selectivity for ethyl‐substituted substrates and products; such an enzyme would be a suitable target for the development of Lepidoptera‐specific pest control products 24. To this end, we undertook the cloning of FPPS cDNAs from two moth species belonging to phylogenetically distant families, Choristoneura fumiferana (Tortricidae) and P. unipuncta (Noctuidae), and analyzed these sequences in the context of two other lepidopteran FPPSs ( Agrotis ipsilon 25 and B. mori 26) that were reported earlier by other groups.…”

Juvenile hormone acid methyltransferase: A key regulatory enzyme for insect metamorphosis

“…Because the JHAMT is an enzyme highly specific to insects, JHAMT inhibitors are expected to be excellent candidates for safe insect growth regulators (IGR). Such IGRs could, via premature reduction of JH titer, induce a precocious lethal metamorphosis and, accordingly, a reduction in the larval feeding stage, and also prevent reproduction in adult stage (38). Moderate similarity of B. mori and D. melanogaster JHAMT peptide sequences enables to clone by homology JHAMT genes from insect pests of agricultural and medical importance.…”