Bioacoustic detection of four Bruchid species in bulk red and green bulk-stored beans

Abstract

Bruchids cause significant damage to stored products. Such damage can be reduced by real-time detection during the early stages of infestation. The sound of movement of adult Callosobruchus chinensis, C. maculatus, C. analis, Zabrotes subfasciatus and the sound of larvae feeding on red beans (Vigna angularis) and green beans (Vigna radiata) at 10, 17, 24, 31, and 38 °C, were recorded using an insect probe that was inserted into the soundproof box. The recorded sounds were analyzed in the time-frequency domain using Cool Edit PRO acoustic software. The characteristic sound parameters were determined by counting and analyzing the pulse numbers of insect sound, the pulse peak of insect sound, the highest frequency of insect sound and the pulse duration of insect sound. The optimal temperature for studying the larvae of four Bruchid species feeding on red beans and green beans was found to be 31 °C. At the optimum temperature, the four Bruchid species larvae could be distinguished by characteristic sound parameters. In the characteristic sound parameters of four Bruchid larvae feeding on red and green beans, there were significant differences respectively in pulse duration among the four Bruchid species (P < 0.05). The result indicated that pulse duration could distinguish four Bruchid. Additionally, the pulse numbers of insect sound in characteristic sound parameters from green beans further enabled differentiation among the four Bruchid species.