Acoustic recording as a non‐invasive method to detect larval infestation of Cosmopolites sordidus

AbstractThe banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), is a major pest of banana cropping systems, as larvae bore into the corm of banana plants and damage the insertion points of primary roots, leading to plant snapping and toppling. Plant infestation by the banana weevil is assessed only via invasive techniques, such as plant cutting that highlights larval tunnels. We present here a non‐invasive technique based on a bioacoustic sensor with a band‐pass filter to detect larval activity inside banana corm. On the basis of a test under controlled conditions, we observed that the range of larval activity was between 1.4 and 2.6 kHz. Pulses lasted ca. 168 ms and were separated by intervals of 300 ms. The technique enables detection of more than 90% of infested suckers. The use of this technique to understand larval development of banana weevil is discussed.