Impact of agrochemicals on non-target species: Calathus fuscipes Goeze 1777 (Coleoptera: Carabidae) as model

Carabid beetles are important in the biological control of arable crop pests. Agricultural practices can produceover time a delayed toxic effect at the organismal and population levels and can compromise the survival onthese species. In this research, we quantified the cumulative sublethal effect on body size, Malpighian tubulesand immune responses in Calathus fuscipes adults living in the potato field and exposed to lambda-cyhalothrinand cymoxanil-based commercial formulates. Reductions of morphological parameters such as body, pronotumand elytron in both males and females from the potato field indicated that the pre-imaginal stages (larvae andpupae) suffer the sublethal effects of exposure to the larvicide control action of lambda-cyhalothrin.Ultrastructural alterations recorded in Malpighian tubules at the level of plasma membrane, mitochondriaand nucleus indicated the reduction of the detoxification capability. The basal phenoloxidase and lysozyme-likeenzyme activities have measured as markers of immune competence. Spectrophometric analyses showed that thechronic exposure in field causes an increase of basal phenoloxidase enzyme activity, while the lytic activity ofhaemolymph was not affected. As a result, the use of larvicides and fungicides have a harmful effect on beneficialspecies such C. fuscipes living in the soil of potato fields. These morphological and physiological results recordedat the organismal level can provide useful information of effects at the population and community levels topreserve the biodiversity of agroecosystem.