Foliar and ground-foraging predators of aphids associated with alfalfa crops in Chile: Are they good or bad partners?

Abstract

Carabids and coccinellids are the most abundant aphid predators in alfalfa. Depending on the amount of prey consumed, the impact of their combined effect can be additive, antagonistic, or synergistic. Laboratory trials demonstrated that a higher proportion of Aphis craccivora Koch dropped from the alfalfa plants in the presence of coccinellids, and that the interaction between these predators was additive or synergistic, but never antagonistic, suggesting that they might be good partners in controlling aphids.

Keywords:

• Aphid consumption
• carabids
• coccinellids
• biological control
• predator–predator interactions

Acknowledgements

This study was funded by the Grant Universidad de Chile EN 05/2 to AA Grez and partially by FONDECYT 1070412. The authors would like to thank Mario Elgueta for helping with the carabid species identification, Alberto Mansilla, for his advice in the statistical analyses, Charles Pickett and two anonymous reviewers for their helpful comments to an earlier version of this manuscript.