Host‐marking by female pepper weevils, Anthonomus eugenii

Abstract

Pepper weevils, Anthonomus eugenii Cano (Coleoptera: Curculionidae), feed and oviposit in flower buds and small fruits of plants in the genus Capsicum, as well as several species of Solanum (Solanaceae). Females chew a small hole into the fruit, deposit a single egg within the cavity, and seal the hole with a clear anal secretion that hardens into an ‘oviposition plug’. Female oviposition behavior was studied in a series of small‐arena bioassays to determine whether previous oviposition in Jalapeño pepper fruit deterred subsequent oviposition and to determine what specific cues from an infested fruit influence female behavior. In choice and no‐choice tests, females preferred clean fruit to fruit that had received four eggs 24 h previously (i.e., infested fruit), whether the fruit was infested with conspecific eggs or their own eggs. Further bioassays demonstrated that the presence of female frass, or oviposition plugs alone, in the absence of eggs or any fruit damage, was sufficient to deter oviposition. In addition, females given the choice between an infested fruit with the oviposition plug removed or an unaltered infested fruit preferred the fruit with no plugs, even when eggs, frass, and feeding damage were still present. To determine whether females would avoid infested peppers under more natural conditions, we quantified oviposition on infested and uninfested sentinel pepper fruit within individually caged plants and on clean and infested plants caged together. Females consistently laid more eggs on clean fruit than on infested fruits and moved within and among pepper plants to search for more acceptable oviposition sites. We conclude that oviposition plugs, along with contaminated female, but not male, frass contain a deterrent that, in the absence of any other cue, is enough to alert a female that a patch is occupied.

Evolution of cannibalism and female’s response to oviposition‐deterring pheromone in aphidophagous predators

“…The choice of oviposition sites is therefore crucial and has a large effect on the fitness of females (Resetarits 1996). Many insect species, whose food supplies are temporally limited, avoid the risk of competition between conspecific offspring by marking the resource (Gabel & Thiery 1992;Ruzicka 1996Ruzicka , 1997Dempster 1997;Ruzicka & Havelka 1998;Anbutsu & Togashi 2001;Addesso et al 2007;Liu, Yu & Li 2008). For instance, parasitoids avoid superparasitism by probing potential hosts (Agboka et al 2002;Yamada & Ikawa 2005) or marking them with pheromones, which facilitates the detection of conspecifics within a host (Vandijken, Vanstratum & Vanalphen 1992;Visser et al 1992;Gauthier, Monge & Huignard 1996;Field & Keller 1999;Santolamazza-Carbone, Rodriguez-Illamola & Rivera 2004).…”

“…The choice of oviposition sites is therefore crucial and has a large effect on the fitness of females (Resetarits 1996). Many insect species, whose food supplies are temporally limited, avoid the risk of competition between conspecific offspring by marking the resource (Gabel & Thiery 1992; Ruzicka 1996, 1997; Dempster 1997; Ruzicka & Havelka 1998; Anbutsu & Togashi 2001; Addesso et al. 2007; Liu, Yu & Li 2008).…”

Evolution of host plant use and diversification in a species complex of parasitic weevils (Coleoptera: Curculionidae)

“…Mediated by marking pheromones, many parasitoids and phytophagous insects avoid hosts already infested by conspecifics or closely related species (Anderson, 2003; Nufio & Papaj, 2001; Roitberg & Prokopy, 1987). In beetles, there is evidence that ovipositing females of some species within the families Chrysomelidae (Guedes & Yack, 2016; Messina & Renwick, 1985) and Curculionidae (Addesso et al, 2007; Ferguson et al, 1999) avoid hosts and plant structures that have been previously utilized by other females for laying eggs. Hence, driven by chemical constraints, the use of a restricted set of host plants over evolutionary time scales may lead to inter- and intraspecific competition which in turn could facilitate an escape-and-radiate scenario (Ehrlich & Raven, 1964) where weevils “escape” to different plant structures, potentially undergoing diversification.…”

A Modelling Approach to Describe the Anthonomus eugenii (Coleoptera: Curculionidae) Life Cycle in Plant Protection: A Priori and a Posteriori Analysis

“…Because A. eugenii may develop on both wild and cultivated Solanum and Capsicum (both Solanaceae) species, insect control strategies often are difficult to implement successfully, because nightshade-residing populations are able to re-infest cultivated pepper fields the following season (Addesso et al 2007). Damages are inflicted primarily by the trophic activities of the larvae and adults.…”