Host utilization by the pepper weevil (Anthonomus eugenii): suitability, preference and offspring performance

BACKGROUND Host plant selection is a key factor affecting the survival, population establishment, and spread of herbivorous insect pests. The pepper weevil is one of the most important pests of cultivated pepper in North America with a capacity to rapidly expand its geographic range, in part through its ability to switch between cultivated and wild Solanaceous host plants. Towards a better management of this pest, this study examined metrics of pepper weevil host use including oviposition preference, development time, and successful offspring emergence on wild Solanaceous species and cultivated pepper cultivars. RESULTS Pepper weevil successfully developed within fruit of several Solanaceous species including eastern black (Solanum ptycanthum) and climbing nightshade (S. dulcamara), in which development time was on average 4 days faster relative to Capsicum annuum cv. jalapeno peppers. Oviposition events occurred in all fruit types assessed and no strong host preference was detected among these. However, the number of emerged offspring was significantly lower than the number of oviposition events in C. chinense cv. habanero pepper fruit. CONCLUSION Although not all nightshade species are suitable hosts for pepper weevil development, those permissive to offspring production do allow for faster development than in C. annuum peppers. While host preference was not detected among fruit types tested, low offspring emergence from fruit with high capsaicin content suggests a reduced ability of pepper weevil to tolerate high concentrations of this metabolite. These findings help elucidate the factors influencing pepper weevil bionomics, and their implications on pepper weevil management are discussed.

Automated summary

This study found that the pepper weevil could successfully develop in several wild Solanaceous species, with faster development time compared to pepper fruit. Although no strong host preference was detected among the fruit types tested, low offspring emergence was observed in fruits with high capsaicin content.