Tobacco whitefly (Bemisia tabaci) was found by Defra plant health inspectors last year on finished poinsettias imported from Germany and the Netherlands, resulting in more than 80,000 plants being destroyed.
The pest continues to be brought into the UK on imported poinsettia cuttings and recent research has indicated the development of insecticide resistance, meaning that control will become even more difficult.
The briefing note gives information on the biology of the pest and available controls. They include programmes based solely on biological agents, integrated pest management incorporating biological agents and compatible insecticides, and chemical programmes.
The note gives details of a recent HDC project that tested sequential applications of a range of chemicals in the Food & Environment Research Agency laboratories in York. The results showed that all the programmes gave complete control of the Q strain of tobacco whitefly, so could be selected for immediate commercial use.