Abstract
To inform government policy at national and European scales, Defra needs to be well informed about the many factors that influence the sustainability and environmental impacts of arable crop production. This project will maintain consistency of surveillance of diseases and pests in winter wheat and winter oilseed rape (the two most important combinable crops in the UK), an initiative which has been undertaken by Defra for a period of over 30 years. These data will be used to assess changes in pest and pathogen prevalance and to monitor trends in agronomic practice for pest and disease management. Three hundred winter wheat fields and one hundred winter oilseed rape fields, stratified by region and arable farm size, will be selected at random from a list of farms in England derived from annual returns to Defra Census Branch. A subset of wheat fields will be assessed for aphid levels at late flowering and then crop samples will be taken from all fields at GS75 (milky ripe growth stage) and assessed for foliar, stem-base and ear diseases. A questionnaire will be used to obtain background details for the crop including cultivar, tillage practice, sowing and harvest date, previous cropping and pesticides use, which are key factors with potential to affect pest and/or pathogen levels. The winter oilseed rape crops will be assessed on three occasions (autumn (mid-leaf production), spring (early stem extension) and summer (pod ripening). Samples taken in the autumn and spring will be assessed for all foliar, stem and root diseases and the presence of cabbage stem flea beetle and rape winter stem weevil. In the summer, selected crops, which have not been treated with insecticide, will be assessed in situ on two occasions (at green to yellow bud and at mid to late flowering) for presence of pollen beetle (Meligethes spp.), cabbage seed weevil (Ceutorhyncus assimilis) and cabbage stem weevil. A final assessment will then take place on all crops at pod ripening to measure stem, root and pod disease levels. As for the wheat survey, a questionnaire will be used to obtain specific details of agronomic practice. Additional investigations will be carried out on wheat crops affected by Fusarium head blight which is a disease caused by a complex of at least five pathogen species, some of which produce mycotoxins which contaminate harvested grain. Identification of the species present and the toxins they produce will assist in monitoring the annual severity of this disease, measure changes in prevalence of each species in response to climate and agronomic practice and provide data to assist in risk analyses for mycotoxin contamination in grain. The datasets generated from these annual surveys now provide Defra with statistically sound data sources that have the resolution and flexibility necessary to inform a wide range of policy questions now and for the future. The historical reference datasets identified are used and quoted widely across government, academia and industry and form a reliable evidence base to inform Defra initiatives. In line with Defra’s need, this evidence base is dynamic, changing as research delivers new tools and understanding, and provides a mechanism to analyse issues that were previously thought to be unconnected. This project will provide the only impartial and statistically robust source of evidence for policy making which aims to mitigate the impacts of crop diseases and pests and unsustainable management practices. The data collected are also a key resource for monitoring impacts of climate change on UK agriculture by measuring indicator species. Most recently these data were used to examine the impacts of revisions to Directive 91/414/EEC, affecting future availability of pesticide active ingredients, to production of wheat in this country. As well as addressing future research and policy needs, this project will continue existing collaborations with a wide range of Defra and levy funded research and industry projects through provision of data for investigation of the impacts of issues including food security, climate change, environmental protection, UK and EU government policy, varietal resistance, pathogen resistance, land management and economics on wheat and oilseed rape production. Samples or data will also be provided to support monitoring for food safety, development and validation of models for disease and pest forecasting and identification of sustainable crop management strategies for the industry.
United Kingdom