Bruchid beetles are important pests of field and stored legumes, causing great economic losses. The main pest species are Callosobruchus maculatus, Acanthoscelides obtectus and Zabrotes subfasciatus. Modified atmospheres (MAs) with high carbon dioxide (CO2) content are environmentally friendly pest control methods for stored products. They are effective in controlling a wide range of species and can be used to treat different food products without leading to an accumulation of toxic residues. The present study aimed to establish the efficacy of using MAs with high CO2 to control all developmental stages of these three bruchid pest species. Three high CO2 MAs (50%, 70% and 90%) were tested at 28°C. In general, pupae and/or eggs were the most tolerant stages to hypercarbia, while adults were less tolerant. The susceptibility of eggs varied greatly according to their phase of development and the pattern was different in the three species tested. Tolerance of other stages to CO2 also varied among the three bruchid species. To achieve total mortality of Z.subfasciatus, a maximum of 9-11 days were needed, depending on CO2 concentration, to kill the eggs. This stage and the pupae were the most tolerant stages. However, in A.obtectus and C.maculatus, only pupae were the most tolerant and required 9 days to be killed, their eggs being more sensitive to CO2.
Bibliographical noteFunding Information:
This work was partially financed by a grant from the Instituto Nacional de Investigación Agraria y Alimentaria RTA 2011-00025-C02-01 (FEDER), and the grant number 77 from the “ Programa de beques de recerca per a professors i professores i investigadors i investigadores visitants a Catalunya 2010 (PIV-DGR) ” of the “CUR del DIUE de la Generalitat de Catalunya” awarded to the first author. We are also grateful to Carburos Metálicos-Air Products Group for providing gases and laboratory equipments.
- Acanthoscelides obtectus
- Callosobruchus maculatus
- Pest control
- Zabrotes subfasciatus