Attraction and fecundity of adult codling moth, Cydia pomonella, as influenced by methoxyfenozide-treated electrostatic powder

Codling moth, Cydia pomonella (L.), remains a principal insect pest of tree fruit orchards throughout the temperate regions of the world (Barnes 1991; Beers et al. 1993). Its larvae bore deep into the fruits of apple, pear and walnut making them unmarketable. The majority of conventional growers still rely on chemical insecticides to control this insect. However, concerns regarding development of insecticide resistance, food safety, environmental contamination, and negative effects on non-target organisms necessitate the development of alternative controls. Loss of registered compounds such as azinphos-methyl limits the insecticidal options for controlling C. pomonlla. This increases the need for pursuing more selective insecticides as well as reliable delivery systems to: improve the efficiency of insecticide application, minimize impacts on non-target organisms, and reduce insecticide contamination of the environment. Methoxyfenozide, the newest and most effective member of the diacylhydrazine class, has very high affinity for ecdyseteroid receptors in Lepidoptera, where it mimics the insect molting hormone, 20hydroxyecdysone (Carlson et al. 2001). Thus, it is highly toxic to a range of economically important lepidopteran larvae such as Spodoptera littoralis (Boisduval) (Pineda et al. 2007), Lobesia botrana (Denis and Schiffermuller) (Irigaray et al. 2005) and Ostrinia nubilalis (Hübner) (Trisyono and Chippendale 1997); but it is less harmful to non-target organisms than are conventional insecticides. This compound is essentially non-toxic to adult Lepidoptera by either oral or topical administration (Carlson et al. 2001). However, several studies have reported some effects on fecundity (numbers of eggs laid) and egg hatching following exposure to methoxyfenozide (Sun and Barrett 1999; Sun et al. 2000; Hoelscher and Barrett 2003a,b). For example, exposure to methoxyfenozide-treated surfaces reduced fecundity and