Common sowing rates of major European field crops: Results of a large-scale farmer survey

In the European Union (EU), pesticides can only be used by farmers after an acceptable risk to consumers, operators, and the environment has been demonstrated. Plant protection products applied as seed treatments have several environmental advantages compared with foliar spray applications, especially lower use rates and less drift to off-crop habitats. Regulatory risk assessments for seed treatment products in the EU are routinely based on maximum ‘commonly used’ sowing rates. Such assessments may overestimate the true risk as sowing rate distributions can be skewed by atypically high sowing rates, which are often a result of localized conditions. To have a better view of realistic worst-case sowing rates for key field crops (cereals, maize, oilseed rape, sunflower, soybean and sugar beet) grown in the EU, a large-scale farmer survey was conducted in 2020 and 2021 across a representative range of EU countries, and the United Kingdom. The total number of farmers interviewed ranged from 112 (spring oilseed rape) to 14 479 (winter wheat). The number of countries from which farmers were interviewed ranged from three (spring oilseed rape) to 17 (winter wheat). Mean and 90th percentile values of sowing rates were calculated from the survey results per crop and are proposed as more representative worst-case values for use in seed treatment regulatory risk assessments.