Geranyl hexanoate, the female-produced pheromone of Agriotes sordidus Illiger (Coleoptera: Elateridae) and its activity on both sexes

Abstract

Analysis of the pheromone gland extract of females of the click beetle Agriotes sordidus (Illiger), revealed the presence of geranyl hexanoate (GH) and (E,E)-farnesyl hexanoate (FH) in an approximate ratio of 1:1. In the female-released volatiles collected by headspace extraction, GH was a dominant component with FH present only in trace amounts. In field trapping tests GH on its own captured high numbers of A. sordidus adults, whereas the addition of FH in various proportions had no effect on captures. A closer scrutiny of adults caught in GH-baited traps revealed that 10-40 % of them were females. Significantly higher numbers of both female and male beetles were attracted to traps baited with GH as compared to unbaited controls showing a clear dose-response relationship with higher doses catching more beetles. In electroantennogram (EAG) tests responses of female and male antennae to a number of known click beetle pheromone components showed the same trend in both sexes, giving the highest answers to GH. This suggests that female and male antennae are similar with respect to the perception of pheromone components, and that GH shows some activity as an aggregation pheromone.

Environmentally vulnerable noble chafers exhibit unusual pheromone-mediated behaviour

“…Such a response to a volatile pheromone may reflect an intermediate evolutionary stage towards developing into a sex-specific signal [ 27 ]. Similar, although not identical, evolving sexual communication systems have been found in Holotrichia consaguinea Blanchard (Coleoptera: Scarabaeidae) [ 28 ] and in Agriotes sordidus Illiger (Coleoptera: Elateridae) [ 29 ]; however, in these cases, both females and males were attracted to the female-produced pheromone. Leal et al [ 28 ] proposed that for H .…”

“…Although not investigated in this study, female G . nobilis likely possess the sensory capabilities to detect the pheromone (autodetection, [ 36 ]), as it was recently described for other members of the Coleoptera [ 29 ].…”

An update of the Worldwide Integrated Assessment (WIA) on systemic pesticides. Part 4: Alternatives in major cropping systems

“…Thresholds have been defined for wireworms (Furlan 2014 ), brown planthopper (Zheng et al 2007 ) and for different cotton pests, including A. gossypii (Silvie et al 2013 ; Sequeira and Naranjo 2008 ). Data input for DSS are regularly collected through field-level monitoring: WCR and wireworms can be monitored using sticky traps, pheromone traps or bait traps (Sufyan et al 2011 ; Vuts et al 2014 ; Benefer et al 2012 ; Parker 1994 , 1996 ; van Herk and Vernon 2013 ; Tóth et al 2002 ; Tóth et al 2007 ; Vuts et al 2012 ; Tóth 2013 ; Tóth et al 2015 ; Furlan et al 2017a , 2017b ; Bažok et al 2011 ; Kos et al 2014 ). In Northern Italy (Emilia-Romagna region) a monitoring net for two wireworm species has been employed in 2017 and 2018 using about 1100 pheromone traps per year, providing provisional threshold to alert farmers on infestation risk.…”

The use of click beetle pheromone traps to optimize the risk assessment of wireworm (Coleoptera: Elateridae) maize damage

“…A. brevis behaves in a similar manner to A. sordidus (overwintering adults 32 ), but has a longer swarming period, which starts slightly earlier than that of A. sordidus 32 . These pheromone traps catch both males and females, although males are prevalent [33][34][35] .…”