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Αλέξανδρος Γ. Σφακιανάκης

Saturday, June 29, 2019

Pest categorisation of non‐EU Cicadomorpha vectors of Xylella spp.

Abstract

The Panel on Plant Health performed a group pest categorisation of non‐EU Cicadomorpha vectors of Xylella spp. known to be associated with plant diseases. Although all the insects considered in this categorisation are proven vectors of Xylella spp., additional vectors within the order Hemiptera most probably exist but have not been associated with any Xylella spp. disease yet. Currently, the group consists of 50 taxa (49 at species level and one at genus level) from the families Aphrophoridae, Cicadellidae and Membracidae (Arthropoda: Hemiptera: Cicadomorpha) for which reliable identification methods exist. Members of the group can be found in the Americas, Asia, Africa and Oceania. Only one of them, Homalodisca vitripennis is considered invasive. Species in the group are mostly polyphagous; many are known to feed on several plant families. Hosts can include broadleaf trees, herbaceous plants and grasses. Breeding takes place on herbaceous hosts and eggs are inserted into plant tissues. Nymphs emerge to feed on sap of the natal host. Adults move from breeding hosts to food hosts and can spread Xylella spp. causing a variety of diseases. Three of the species are listed in Annex IAI of Council Directive 2000/29/EC as examples of Cicadellidae (non‐EU) known to be vector of Pierce's disease (caused by Xylella fastidiosa). Plants for planting, cut branches, flowers and fruit are potential pathways for entry into the EU. However, there are no records of EU interceptions of any members of the group. EU biotic and abiotic conditions are conducive for establishment and spread of these insects. Were members of the group to establish and spread, impact on several cultivated species (e.g. grapevine, citrus, Prunus spp.) and ornamentals (e.g. Polygala myrtifolia) could be expected as these insect species are efficient vectors of Xylella spp. Considering the criteria within the remit of EFSA to assess their regulatory plant health status, the group of non‐EU Cicadomorpha vectors of Xylella spp. meets all the criteria assessed by EFSA for consideration as potential Union quarantine pests. The group does not meet all the criteria assessed by EFSA for consideration as regulated non‐quarantine pests, as members of the group are not present in the EU.

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