Effects of the Insect Growth Regulator, Methoprene, onOnthophagus taurus(Coleoptera: Scarabaeidae)

Abstract

A bioassay was conducted to determine the impact of methoprene, an insect growth regulator (IGR), on fecundity, larval survival, and size of progeny for Onthophagus taurus Schreber. Adult O. taurus dung beetles were offered methoprene-treated manure in three to five replications each at concentrations of 0.08, 0.45, and 4.5 ppm, respectively. An additional group of adult beetles was immersed in a methoprene-water solution and allowed to reproduce in containers with untreated manure. Data from all treatment groups were compared with untreated control groups. Methoprene did not seem to hinder brood production at 0.45 ppm. Survival of O. taurus was not affected by methoprene-treated manure at 0.08 ppm or when parent beetles were immersed in methoprene-water solution. However, progeny survival was significantly reduced on manure treated with methoprene at 4.5 ppm. Mean pronotal width of O. taurus progeny was significantly smaller in beetles fed methoprene-treated manure (4.5 ppm). The low dose of 0.08 ppm did not affect pronotal widths nor did topical application of methoprene to adults affect pronotal widths in resulting offspring. Although some adverse effects of methoprene were observed at higher concentrations, use of methoprene at concentrations of 0.08 ppm as part of a horn fly control program likely would not greatly affect populations of O. taurus, the most common paracoprid dung beetle in North Carolina.

Field and Laboratory Evaluation of Bioefficacy of an Insect Growth Regulator (Dimilin) as a Larvicide against Mosquito and Housefly Larvae

“…Larviciding involve the use of both chemical insecticides and the insect growth regulators (IGR) in controlling larvae of various insect pests [14–16]. The IGRs, unlike the chemical larvicides, are strictly arthropod-specific and environmental safe [17].…”

Physiological and Biochemical Effect of Pyriproxyfen on Indian Meal Moth Plodia Interpunctella (Hübner) (Lepidoptera: Pyralidae)

“…Egg production in Rhyzopertha dominica Fabricius (Coleoptera: Bostrichidae) was significantly reduced by treatment with methoprene and it simultaneously affected egg hatchability (Chanbang et al 2008). Progeny survival was significantly reduced with methoprene in Onthophagus taurus Schreber (Coleoptera: Scarabaeidae) (Nino et al 2009). Another JHA, hydroprene, is considered to be an alternative to conventional insecticides because of its specific activity against immature insect stages, low persistence in the environment, and nontoxic effect on mammals (Mohandass et al 2006).…”

Effects of juvenile hormone analogue treatment in adult females of the ovoviviparous cockroach,Blaptica dubia(Dictyoptera, Blaberidae)

“…Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions Introduction Insect growth regulators (IGR) act as hormone analogues or anti-hormones and induce a variety of morphogenetic, developmental and reproductive effects in insects (Dhadialla et al 1998;Dhadialla et al 2005;Retnakaran et al 1985). IGR are one of the most promising alternatives to conventional insecticides and are widely used to control pests (Ishaaya 1990;Langley et al 1993;Liu 2003;Miyamoto et al 1993;Maiza et al 2004;Nino et al 2009;Oberlander et al 1997;Sun et al 2013;Tunaz and Uygun 2004;Yu 2008). Juvenile hormone (JH) analogues, such as methoprene, hydroprene, kinoprene, fenoxycarb or pyriproxyfen, disrupt larval and adult development by mimicking the action of JH (Sehnal 1983).…”