Promotores: P.G.L. Klinkhamer, P.M. Brakefield, Co-Promotor: M. Bruinsma
|Links||Thesis in Leiden Repository|
In this thesis, patterns of variation in plant metabolomes and insect communities were described in GM and non-GM potato plants in both laboratory and field experiments. Differences between plant genotypes in insect abundances were small when compared to year-to-year differences, location effects and differences between developmental stages of plants. Standardized effect sizes are discussed as an alternative scale for measuring effects. Leaf age, aphid infestation and virus infection were found to cause significant alterations in leaf metabolism in a laboratory study as measured by 1H NMR. However, these changes were similar in quantity and quality in both GM and non-GM plants. Furthermore, 1H NMR metabolomic profiles of potato plants were measured in a 2-year field study. Large changes in metabolomic profiles occurred across years and locations, and throughout the growth period of plants within years. Only weak relationships were found between metabolomics data and insect abundances on the same experimental fields. GxE interactions imply that conclusions from field trials are not valid outside the range of tested environments. This emphasizes the need for a careful choice of representative geographical zones for risk assessment studies. However, it also shows that a residual level of uncertainty in NTO safety is unavoidable.