The western corn rootworm, a new threat to European agriculture: opportunities for biotechnology?

During the early 1990s, the western corn rootworm, Diabrotica virgifera virgifera Le Conte (WCR), a maize pest, invaded the European continent. The continuous spread of the pest has introduced a new constraint into European maize production. As the damage caused by the invasive species is highly variable and different crop protection (CP) strategies are available, farmers' optimal strategies are not obvious. This study uses a simulation model to assess the competitiveness of different CP strategies in seven Central European countries.

Results indicate a high degree of heterogeneity in the profitability of different CP strategies, depending on the production parameters in each country. In general, crop rotation and Bt maize offer the best solutions to farmers, but, in continuous (non-rotated) maize cultivation, chemical CP options may capture part of the market. For Austrian continuous maize production it is found that not deregulating Bt maize implies that farmers forego revenues of up to euro 59 ha(-1).

In the presence of WCR, producing maize by an economically sound method requires incorporating country- and farm-specific characteristics into the decision framework. Also, not deregulating Bt maize has direct monetary consequences for many farmers that could influence total maize output and resistance management.