The Addition of a Pheromone to a Floral Lure Increases Catches of Females of the Click Beetle Agriotes ustulatus (Schaller) (Coleoptera: Elateridae)

Abstract

Agriotes ustulatus is an economically important click beetle in Europe. A female-produced pheromone, ( E,E )-farnesyl acetate, has been identified and is used for monitoring and detecting males. More recently, a floral lure targeting females with modest, but significant, activity has been described. Based on preliminary data, we hypothesized, that similar to the effects on the congeneric A. brevis , addition of the pheromone to the floral lure should improve female A. ustulatus catches. Also, as click beetles have been reported to respond to white light, we studied possible interactions between visual and chemical cues. In field trials, the addition of the synthetic pheromone to the floral lure resulted in a dramatic increase in the number of females trapped, whereas male catches remained unaffected and equal to those in traps baited with pheromone only. A white visual cue did not influence trap catches. Maximum catches of both sexes of A. ustulatus can be achieved using the pheromone and the floral lure inside the same trap. Furthermore, the compounds can be formulated in a single polyethylene bag dispenser, making handling of the trap easier. Due to a much larger proportion of females in the catch, this improved trap may be a promising tool for semiochemical-based, environmentally sound agricultural practice against this important pest.

Comparative Antennal Morphology of Agriotes (Coleoptera: Elateridae), with Special Reference to the Typology and Possible Functions of Sensilla

“…Agriotes, as an important agriculture pest, serves as a good model taxon for pest control and management [1][2][3][4]6]. Numerous studies focused on pheromone composition in several Agriotes species [11,[13][14][15][16][17][18][19][20][21][22][23][24][25] in order to develop effective species-specific pheromone traps. However, our knowledge of the sensillar equipment, including the typology and functions of different sensilla, has been highly underexplored.…”

Assessment of the Attraction Range of Sex Pheromone Traps to Agriotes (Coleoptera, Elateridae) Male Click Beetles in South-Eastern Europe

“…This strategy does not theoretically require a 100% catch, or the vast majority of male beetles to be caught in a short space of time, since the killing agent would spread through the population, coming into increasing contact with both male and female adult beetles. Sex pheromones also perform as aggregation pheromones and attract significant numbers of females, as demonstrated for A. sordidus, A. brevis and A. ustulatus [53][54][55]57]. This may further increase entomopathogenic infections in click beetle populations.…”

“…Vernon et al [52] also remark that these costs would currently be unaffordable for an arable crop farmer. Nor can this large-scale trap deployment prevent females entering the treated field from outside, as they are attracted by floral volatiles [53][54][55]. It is also impossible to prevent a portion of the uncaptured males mating with many females, which means that some eggs will always be laid.…”

Alternative Strategies for Controlling Wireworms in Field Crops: A Review

“…This strategy does not require a 100% catch, or the vast majority of male beetles to be caught in a short space of time, since the killing agent would spread through the population, coming into increasing contact with both male and female adult beetles. At least in some click beetles, sex pheromones also perform as aggregation pheromones, and they can also attract significant numbers of females, as demonstrated for A. sordidus, A. brevis, and A. ustulatus [184][185][186][187]. This may be an additional pathway to increasing entomopathogen infections in click-beetle populations and further reducing wireworm pressure on crops.…”