Approaches to pest management in organic agriculture: a case study in European apple orchards

Summary

Although the European organic agriculture movement was founded by Rudolf Steiner and Hans Mueller in the years between 1924 and 1940, it was not until the 1980s that pest management researchers began to develop strategies to control pests in organic systems. Today, insect pest management in organic agriculture involves the adoption of scientificallybased and ecologically sound strategies as specified by international and national organic production standards. These include a ban on synthetic insecticides and, more recently, on genetically modified organisms (GMOs). The first phase of an insect pest management program for organic systems is the adoption of cultural practices including diverse crop rotation, enhancement of soil quality by incorporation of specific cover crops and/or the addition of soil amendments, and choice of resistant varieties that help to prevent pest outbreaks. In the second phase, habitat management (e.g. incorporation of hedgerows and wild flower strips) is implemented to encourage populations of pest antagonists. Third and fourth phases of the program include deployment of direct measures such as biocontrol agents and approved insecticides. However, the strategies for pest prevention implemented in the first two phases often obviate the need for direct control measures. Approaches to pest management in organic systems differ from those in conventional agriculture conceptually in that indirect or preventative measures form the foundation of the system, while direct or reactive control methods are rare and must comply with organic production standards. The range of European research activities that support these concepts is illustrated by a case study of rosy apple aphid (Dysaphis plantaginea) control in organic apple production in Switzerland.