The horticultural trade in Europe can be a major route for the spread of pests and diseases. European plant health inspectors are the first line of defence against these risks but the public can also play a major role in the early detection of outbreaks of pests and diseases. In particular, with their interest in and awareness of cultivated plants, gardeners are well situated to identify and report the appearance of new pests and diseases.
Current risks include Xylella fastidiosa
Xylella fastidiosa symptoms on Prunus (cherry).
Xylella fastidiosa
X. fastidiosa is a bacterial pathogen, which has been found in parts of France and Italy, and could have a wide and damaging impact on nursery stock production, urban landscapes and countryside. It causes multiple symptoms including wilts, diebacks, stunts and leaf scorches. The EU is on high alert for this pathogen and we must be especially vigilant in the UK.
Insects and nematodes may also pose a serious risk to plant growing in the garden setting.
Erwinia amylovora
Fireblight is a bacterial disease of certain woody plants from the Rosaceae family. These include common plants such as Amelanchier, Chaenomeles, Cotoneaster, Crataegeus, Cydonia, Eriobotrya, Malus, Mespilus, Photinia davidiana, Pyracantha, Pyrus and Sorbus
Tissues affected by the symptoms of Erwinia amylovora include blossoms, fruits, shoots, and branches. All symptoms are above ground and are typically easy to recognise.
For many years Northern Ireland has been a ‘protected zone’ for fireblight, however, this was relinquished 30 April 2018. Bringing fireblight-susceptible plants into a protected zone is forbidden unless they have a passport indicating that they have been sourced from a fireblight protected zone or a buffer zone.
Adult tobacco whitefly (Bemisia tabaci). Photo courtesy of Fera.
The tobacco whitefly, Bemisia tabaci, is a pest of a wide range of plants, including vegetables, salad crops and ornamentals, and is a vector of more than 110 viruses. It is unlikely to establish outdoors in the UK, but it could establish under protection. Bemisia tabaci is frequently intercepted on ornamentals in the UK, particularly on poinsettia, Nerium oleander and Mandevilla.
Stem nematode, Ditylenchus dipsaci, is one of the most serious plant-parasitic nematodes of temperate regions, including Europe and the Mediterranean area. The pest is becoming more common in the UK, with a significant increase in the number of outbreaks reported in recent years.
