THE APPLICATION OF SCIENTIFIC PRINCIPLES TO PEST RISK ANALYSIS WITH SPECIAL REFERENCE TO KARNAL BUNT
CE SANSFORD and RHA BAKER
Central Science Laboratory, Sand Hutton, York Y04 1 LZ, UK
Background and objectives
The development of risk analysis has been underpinned by advances in several key areas, including epidemiology - understanding the mechanisms of disease spread among plant populations; computer-based tools e.g. geographical information systems (GIS) which enable the preparation of maps highlighting areas at greatest risk from the introduction of new pests; and improved techniques for surveillance of pests or their vectors. The application of scientific principles within PRA results in better-informed decisions and a growth in understanding between trading nations concerning common standards for the assessment and management of risk.
This paper describes the results of evaluating a model predicting disease severity using a GIS to assess the risks of establishment of the pathogen Tilletia indica Mitra, the cause of Karnal bunt within the European Union (EU). Initial reports of infection of seed lots of durum wheat in the USA in 1996 triggered an assessment of the risks associated with EU trade in bread and durum wheat, rye and triticosecale from countries where the disease is known to occur. The key period of infection of cereal crops by the pathogen is between spikelet emergence and anthesis. Analysis of meteorological conditions known to be favourable for disease development in wheat during this period at weather stations within the area where the disease is prevalent in India, and a comparison of climatic conditions at weather stations in the cereal growing areas of the UK during the same phonological period, allowed a measure of the risk of establishment to be made . As a result of this work, amendments to UK and EU plant health legislation were implemented to protect cereal production.
Materials and methods
Results and conclusions