Clarifications on EFSA GMO Panel recommendations on the Insect Resistance Management plan for genetically modified maize MON 810

Following a request of the European Commission, the European Food Safety Authority (EFSA) assessed the concerns raised by Monsanto on the previous EFSA GMO Panel’s recommendations on its insect resistance management (IRM) plan for maize MON 810. EFSA specifically considered the feasibility of its recommendations for sampling target pests in order to optimise the sampling protocols. EFSA recommends the identification of large geographical areas (e.g. Ebro valley in Spain) where maize MON 810 adoption rate and target pest pressure are high. EFSA suggests focusing the collection of the target pest larvae in three ‘sampling zones’ instead of sampling extensively over entire ‘geographical areas’. In response to Monsanto’s concerns, EFSA also re-used the same resistance evolution model as before to assess whether the IRM approach of Monsanto enables the early detection of resistance so that alternative management measures can be adopted to prevent field resistance. Notwithstanding the difficulty to estimate the density-dependent (DD) mortality of target pests, EFSA considered a range of DD values in the new simulations performed with the same resistance evolution model as before. Based on the results of the new model simulations, EFSA concludes that the previous conclusions and recommendations of the EFSA GMO Panel remain valid. EFSA therefore advocates setting the detection limit for resistance allele frequency at 1 % or 3 % depending on the adoption rate of maize MON 810. Moreover, EFSA recommends to annually sample bi-/multi-voltine target pest populations in areas where maize MON 810 adoption rate is at least 60 % of the total cultivated maize.