Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/25/2018
Publication Date: N/A
Citation: N/A Interpretive Summary: The importance of psocids as pests of stored commodities has been increasing globally, and in the development of integrated pest management programs to deal with these insects it is important to have effective tools for monitoring pest population levels. However, limited information is available on the cues that will attract psocids and which could be incorporated into traps. Attraction to specific wavelengths of light has been reported for one species of psocid, Liposcelis bostrychophila, but it is unknown how other psocid species respond to light. In an evaluation of the response of three psocid pest species (Liposcelis entomophila, L. paeta, and L. brunnea) to six wavelengths of light produced by Light-Emitting Diodes (LED) it was shown that L. entomophila females and males were not attracted to any of the wavelengths tested; L. paeta females responded positively to two UV wavelengths (351 and 400 nm) and to green light (527 nm), while males did not respond to any light; and L. brunnea male and female adults responded positively to all six wavelengths evaluated. When given a choice between UV wavelength light and brewer’s yeast, a food attractant previously identified as eliciting strong attraction by many psocid species, more L. paeta males and L. brunnea males and females selected a UV wavelength light than the brewer’s yeast. Females of L. brunnea and L. paeta were attracted to white light when compared to no light, but females of L. entomophila were not attracted to white light. These results show that psocid pests of stored commodities are highly variable in their response to specific wavelengths of light. Although not all species responded to the 351 nm wavelength UV light, it was the most attractive to the most species. A combination of UV light and a food attractant such as brewer’s yeast appears to be the most promising approach for further evaluation with multi-species psocid monitoring devices.
Technical Abstract: Psocids have become global pests of stored commodities as they can cause considerable economic losses, and they are difficult to control because they have developed resistance to many chemical insecticides. Therefore, it is crucial to investigate alternative integrated pest management (IPM) approaches, such as the use of light attraction for monitoring and/or controlling psocids. Light attraction has been studied for Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae) but not for other psocid species. In this study, we investigated the response of three psocid species, Liposcelis entomophila (Enderlein), L. paeta Pearman, and L. brunnea Motschulsky, to six wavelengths of light from Light-Emitting Diodes (LED) in paired-choice pitfall tests. Liposcelis entomophila females and males were not attracted to any of the wavelengths tested; L. paeta females responded positively to two UV wavelengths (351 and 400 nm) and to green light (527 nm), while males did not respond to any light; and L. brunnea male and female adults responded positively to all six wavelengths evaluated. For most of the LEDs that elicited positive responses compared to the blank controls, L. paeta males and L. brunnea males and females also responded positively to the lights compared to brewer’s yeast, a food attractant highly preferred by several psocid species. Females of L. brunnea and L. paeta were attracted to white light when compared with a blank, but females of L. entomophila were not attracted to white light compared to a blank.