Adventitious presence of GMOs in maize in the view of coexistence

The introduction of genetically modified (GM) crops in the European Union (EU) demand specific management. The EU recommendations for the management of different agricultural practices are oriented towards the sustainable agriculture in the frame of flexible coexistence. Coexistence may be affected by the adventitious presence of genetically modified organisms (APGM) in non-GM crops along the supply chain. Various biological and environmental parameters as well as technical management have influence on the occurrence and the degree of APGM. These parameters are being used for the development of preventive coexistence measures in individual EU countries. Applicability of the prescribed coexistence measures is critically reviewed, also in the view of possible introduction of GM maize cultivation in Slovenia. From the review, it is concluded that some coexistence measures are not in line with coexistence principles because they demand excessive work and are sometimes difficult to implement in practice. Alternative cooperation of different cropping systems are discussed for potential future implementation. The review is focused on maize, the predominant GM crop cultivated in the EU and an interesting crop for cultivation in Slovenia.