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

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.