Integrated pest management needs better implementation to provide ecological advantages

Global food production has doubled over the last 60 years to meet rising demands of the growing human population and increasing per capita consumption. However, this has come at a high environmental cost, including strong negative impacts of synthetic pesticides and mineral fertilizers on non-target organisms, human health and food quality.

Agricultural policies in the European Union are promoting organic management and integrated pest management, or IPM, as environmentally friendly alternatives to conventional management. IPM is a decision support system for crop protection in integrated farming, where the main goal is to reconcile ecological preservation with economic profitability through the balanced use of chemical, biological and cultural practices to manage pests.

Is IPM really good for biodiversity?

– Organic management is largely beneficial for biodiversity, including the natural enemies of crop pests. But IPM has been much less scrutinized, says Sasha Vasconcelos, the leading author behind the study.

–  Olive is an important cash crop in the EU. We conducted a meta-analysis based on 294 observations extracted from 18 studies to compare the effects of three different cultivation strategies on biocontrol potential and herbivore pressure, says Mattias Jonsson, another coauthor of the study. The three strategies were conventional management, organic management and IPM.

The scientists also compiled information about the management practices used within each management strategy to assess differences in intensity.

IPM employ chemicals as a first resort

The results show that IPM in olive production is predominantly based on intensive practices, employing chemical control rather than preventive measures as a first resort. Biocontrol potential and herbivore pressure were similar in conventional management and IPM.

– The biocontrol potential was higher in organic crops than in crops under IPM, especially when considering canopy-dwelling natural enemies. Although organic management enhanced biocontrol potential, it also benefitted some olive pests, and in both cases effects were more pronounced in orchards located in warmer climates, says Mattias.

– In its current form, IPM might not significantly affect biocontrol potential or herbivore pressure when compared with conventional olive crop management. We need to shift to a more comprehensive implementation of IPM practices. We need to use proactive measures to promote natural enemies before resorting to chemical control. In addition, greater use of non-chemical inputs might be required for effective regulation of olive pests in organic olive crops, concludes Sasha.