Acoustic detection of pepper weevil larvae: Anthonomus eugenii (Coleoptera: Curculionidae) under laboratory conditions

The pepper weevil (Anthonomus eugenii Cano) poses a critical threat to Florida’s pepper industry, with infestation rates capable of reducing yields by up to 60% in unmanaged systems and causing annual economic losses exceeding $9 million. Traditional detection methods often fail due to the weevil’s endophytic larval development within fruit tissues. Recent advancements in insect acoustics offer a promising, non-destructive approach to early detection. In this study, we utilized sensitive directional microphones within a semi-anechoic chamber to identify larval activity across three pepper cultivars: jalapeño, mini sweet bell, and scotch bonnet. The two dominant acoustic signals recorded in infested fruits were associated with chewing (impulsive, repetitive bursts) and locomotion (low-frequency, irregular rustling). All infested fruits (100%) produced discernible larval sounds, while uninfested control fruits (100%) exhibited only ambient background noise unique to the test environment. Spectral analyses confirmed significant differentiation between infested and uninfested samples, supporting the feasibility of using this method in trade inspections and field assessments. These findings build upon earlier acoustic work targeting hidden pest species and reinforce the practical utility of sound-based diagnostics in pest management. This research holds particular promise for farmers, produce handlers, and border inspectors by enabling rapid, non-invasive screening for concealed A. eugenii infestations in imported or domestic produce. Such technologies can help safeguard national biosecurity and reduce reliance on chemical controls within Integrated Pest Management framework.