Accumulation and variability of maize pollen deposition on leaves of European Lepidoptera host plants and relation to release rates and deposition determined by standardised technical sampling.

摘要: Risk assessment for GMOs such as Bt maize requires detailed data concerning pollen deposition onto non-target host-plant leaves. A field study of on lepidopteran leaves was therefore undertaken in 2009–2012 Germany. During the flowering period, we used situ microscopy at a spatial resolution adequate to monitor feeding behaviour butterfly larvae. The plant-specific were supplemented with standardised measurements release rates and obtained by volumetric monitors passive samplers. In 2010, made 5377 deposited maize, nettle, goosefoot, sorrel blackberry. Overall mean leaf during period ranged from 54 478 n/cm2 (grains/cm2) depending plant species site, while daily values high 2710 n/cm2. Maximum single leaf-deposition reached up 103,000 n/cm2, 95 % confidence-limit upper boundary 11,716 n/cm2. Daily means variation uncovered our are considerably higher than previously assumed. recorded levels more degree magnitude larger actual EU expert risk assumptions. Because total aggregation have been underestimated, larvae actually subjected variable exposure. Higher risks these organisms must consequently be Our results imply that assessments related effects exposure under both realistic cultivation conditions worst-case scenarios revised. Under common conditions, isolation buffer distances kilometre range recommended rather 20–30 m distance defined EFSA.