Interceptions ani outbreaks of Bemisia tabaci in the UK

摘要

The highly polyphagous whitefly, Bemisia tabaci was first found in the UK in 1987. There were 98 outbreaks that year, 95 of them at glasshouses growing poinsettias. The 'poinsettia strain', or B-biotype, vectors over 120 highly damaging plant virusesand is primarily a threat to protected cultivation (especially edible crops) in the UK. The UK maintains a protected zone for B. tabaci and is one of a small number of EU countries free of the pest. Although sporadic outbreaks do occur at protected ornamental propagators, they have always been eradicated, and outbreaks are usually short-lived. Poinsettias are imported as cuttings from a small number of EC countries. This remains the most prevalent pathway for the introduction of B. tabaci to ornamentalnurseries in the UK. However, B. tabaci is also the most commonly intercepted quarantine pest on imported cut flowers and herbs from a large number of non-EC countries. The number of countries supplying ornamental plants to the UK is increasing, as flower-producing and other companies source a wider range of exotic material and also relocate propagation facilities to Asia, Africa and South America. Thus, the potential for introducing non-European and/or insecticide-resistant strains of B. tabaci - as well as new plant viruses - is likely to increase.