Scientific Opinion on the pest categorisation of Verticillium albo‐atrum sensu stricto Reinke and Berthold, V. alfalfae Inderb., HW Platt, RM Bostock, RM Davis & KV Subbarao, sp. nov., and V. nonalfalfae Inderb., HW Platt, RM Bostock, RM Davis & KV Subbarao, sp. nov.

• Main Author: EFSA Panel on Plant Health (PLH)
• Format: Article
• Language: English
• Published: Wiley 2014-12-01
• Series: EFSA Journal
• Subjects: biology; control; distribution; hosts; impact; pathotypes
• Online Access: https://doi.org/10.2903/j.efsa.2014.3927

Abstract The European Commission requested the EFSA Panel on Plant Health to perform a pest categorisation of Verticillium albo‐atrum Reinke and Berthold, the causal agent of Verticillium wilts. V. albo‐atrum causes wilt and plant death, impairing the growth and shortening the lifespan of its hosts. V. albo‐atrum was recently split into three species, V. albo‐atrum sensu stricto V. alfalfae and V. nonalfalfae for which reliable detection and identification methods exist. V. albo‐atrum sensu lato is present in most parts of the EU. The new taxonomic status of the pathogen, and the confusion that existed in the past between V. albo‐atrum sensu lato and V. dahliae, cause uncertainty on its distribution worldwide and in the EU. Based on recent studies, the presence of each of the new species (V. albo‐atrum sensu stricto, V. alfalfae V. nonalfalfae) has so far been confirmed in a relatively small part of the EU. The pathogen has a wide host range. In the EU, it affects many cultivated and non‐cultivated plant species, including some very important crops (alfalfa, cotton, hop, potato and tomato). However, the so far known host range of each of the above‐mentioned new species is more restricted than that of V. albo‐atrum sensu lato. There are no obvious ecoclimatic factors limiting the potential establishment and spread of the pathogen in the non‐infested part of the EU where hosts are present. Once established, the pathogen can spread by natural and human‐assisted means. Movement of infected host plants for planting, especially asymptomatic plants, can introduce the pathogen into new areas. Integrated management strategies may reduce impacts of V. albo‐atrum sensu lato in the EU, but they do not eliminate the pathogen. V. albo‐atrum sensu lato is listed in Annex IIAII of Directive 2000/29/EC. Despite its wide host range, it is regulated only on Humulus lupulus.