Results from ten years of post-market environmental monitoring of genetically modified MON 810 maize in the European Union.

In European regulations for the deliberate release into the environment of genetically modified organisms (GMO), the objective of General Surveillance in Post-Market Environmental Monitoring is defined as the identification of the occurrence of adverse effects of the GMO or its use which were not anticipated in the environmental risk assessment (ERA). Accompanying the commercial cultivation in the EU of maize event MON 810, General Surveillance was implemented by Monsanto, the authorization holder, on a voluntary basis. We carried out a statistical analysis on the pooled results of ten years of farmer questionnaires, which were a part of this General Surveillance, amounting to 2,627 farmer fields in eight European countries in the period 2006-2015. This analysis did not reveal any unexpected adverse effects associated with the cultivation of MON 810. Results from farmer questionnaires confirmed that the cultivation of MON 810 resulted in a significant reduction in the use of pesticides, efficient protection against the target pests, and healthier, higher yielding crops compared to conventional maize. MON 810 also had reduced susceptibility to disease and pests when compared to conventional maize. Monitoring characteristics related to environment and wildlife revealed no significant differences between MON 810 and conventional maize. Literature searches, that were also conducted as part of General Surveillance, identified a comprehensive set of publications addressing environmental safety as well as food and feed safety aspects of MON 810. None of the publications indicated any adverse effect of MON 810 that was not anticipated in the initial ERA, nor did they lead to a change in the conclusions of the initial risk assessment that demonstrated the safety of MON 810. The development of resistance by the target pests (Ostrinia nubilalis, ECB and Sesamia nonagrioides, MCB) was the only potential adverse effect identified in the ERA of MON 810 cultivation in the EU. The extensive safety data package for MON 810, the robust weight of evidence demonstrating both its safety and benefits, and the history of safe use of MON 810 for 15 years in the EU, indicates that focussing the General Surveillance of MON 810 on literature searches and farmer complaint systems would be appropriately protective. This will allow the identification of potential adverse effect not anticipated in the initial ERA without the intensive effort and organizational challenges of farmer questionnaires.

Different levels of glyphosate-resistant Lolium rigidum L. among major crops in southern Spain and France.

Herbicides are the most effective tools for controlling almost 99% of weeds. However, herbicide resistance is a primary concern in modern agriculture. The characterization in new areas and elucidation of the mechanisms of resistance are of vital importance in maintaining the sustainability of herbicides, including glyphosate. Nine populations of Lolium rigidum, showing different response patterns, were characterized as being glyphosate resistant (GR). The wide range of values in fresh weight reduction, survival, shikimic acid and EPSPS enzyme activity indicates a different or a combination resistance mechanism. The Line-3 population resulted in minimum reduction of fresh weight and survival values with respect to the glyphosate-susceptible (GS) population, showing 16.05- and 17.90-fold higher values, respectively. There were significant differences in the 14C-glyphosate translocation between GR and GS populations. Moreover, there were differences among the nine GR populations, but they exhibited a reduction in the remaining glyphosate translocation in the treated leaf. The EPSPS gene sequence revealed a Pro-106-Ser substitution in four populations, which could be characterized as being GR with non-target-site and target-site resistance mechanisms. This complexity of several resistance mechanisms makes it necessary to develop long-term integrated weed management strategies to limit further resistance dispersal.

Target site mutation and reduced translocation are present in a glyphosate-resistant Lolium multiflorum Lam. biotype from Spain.

The resistance mechanism of a glyphosate-resistant Lolium multiflorum Lam. biotype collected in Córdoba (Southern Spain) was examined. Resistance Factor values at three different growth stages ranged between 4.77 and 4.91. At 96 hours after treatment (HAT) the S biotype had accumulated seven times more shikimic acid than the R biotype. There were significant differences in translocation of (14)C-glyphosate between biotypes, i.e. at 96 HAT, the R biotype accumulated in the treated leaf more than 70% of the absorbed herbicide, in comparison with 59.21% of the S biotype; the R biotype translocated only 14.79% of the absorbed (14)C-glyphosate to roots, while in the S population this value was 24.79%. Visualization of (14)C-glyphosate by phosphor imaging showed a reduced distribution in the R biotype compared with the S. Glyphosate metabolism was not involved in the resistance mechanism due to both biotypes showing similar values of glyphosate at 96 HAT. Comparison of the EPSPS gene sequences between biotypes indicated that the R biotype has a proline 182 to serine amino acid substitution. In short, the resistance mechanism of the L. multiflorum Lam. biotype is due to an impaired translocation of the herbicide and an altered target site.