Control of Callosobruchus maculatus (Coleoptera: Chrysomelidae) with natural enemies in chickpeas

Abstract: Callosobruchus chinensis is the main pest of stored chickpeas. A limited number of highly toxic pesticides are repeatedly used for its control during the storage period. This leads to residue problems in the grain and the appearance of resistant populations of the pest, which is why it is necessary to develop alternative control methods. The use of natural enemies is a possible alternative that can be very effective in legume warehouses. In this study, two egg predatory mites and two larval parasitoids were evaluated in the laboratory for the control of this weevil. The two predatory mites, Blattisocius tarsalis and Amblyseius swirskii, were able to survive in the low humidity conditions of many warehouses. However, the number of eggs that they consumed was not very high. In comparison, the parasitoids Anisopteromalus calandrae and Lariophagus distinguendus were very effective, causing mortalities greater than 90% of the weevil population. These parasitoids were able to effectively parasitize the host at depths up to one and a half meters in 20 cm diameter tubes filled with chickpeas that simulated the depth at which parasitoids would have to penetrate within a pile. Moreover, A. calandrae was very efficient in controlling C. chinensis when released in commercial polypropylene bags of 25 kg chickpeas. Thus, both parasitoids can be an effective alternative for the control of this weevil.