Analysis of risk posed by plant pest introductions.
Globalization has deeply transformed economic flows across the world, with increased movement of materials and goods, and increased circulation by people. These changes have high potential impacts on the long-range movements of harmful organisms for plants. Whenever introduced in a new area, these organisms can experience favourable conditions for establishment and spread because of the absence of their natural enemies or antagonists, with severe effects on the local agro-ecosystems from an economic, social and environmental point of view. Pest Risk Analysis (PRA) is a decision-support scheme for deciding whether an organism has the characteristics of a plant pest for a clearly defined area (quarantine pest) and if appropriate for selecting the risk management options to be applied according to the IPPC, International Plant Protection Convention. Currently the PRA has some constraints: (i) it produces evaluations rather than quantitative estimates of the risk, (ii) it is subjective, (iii) it does not sufficiently account for uncertainty. New approaches based on mathematical modelling and statistical methods for quantitative estimation of the risk can produce important improvements of the current PRA schemes and increase objectivity.