Pest categorisation of Neoscytalidium dimidiatum.

Abstract

The EFSA Plant Health Panelperformed a pest categorisation of Neoscytalidium dimidiatum, a clearly defined plant pathogenic fungus of the family Botryosphaeriaceae. The pathogen affects a wide range of woody perennial crops and ornamental plants causing symptoms such as leaf spot, shoot blight, branch dieback, canker, pre- and post-harvest fruit rot, gummosis and root rot. The pathogen is present in Africa, Asia, North and South America, and Oceania. It has also been reported from Greece, Cyprus and Italy, with a restricted distribution. Nevertheless, there is a key uncertainty on the geographical distribution of N. dimidiatum worldwide and in the EU, because in the past, when molecular tools were not available, the two synanamorphs of the pathogen (Fusicoccum-like and Scytalidium-like) might have been misidentified based only on morphology and pathogenicity tests. N. dimidiatum is not included in Commission Implementing Regulation (EU) 2019/2072. Because of the wide host range of the pathogen, this pest categorisation focuses on those hosts for which there is robust evidence that the pathogen was formally identified by a combination of morphology, pathogenicity and multilocus sequence analysis. Plants for planting, fresh fruits and bark and wood of host plants as well as soil and other plant growing media are the main pathways for the further entry of the pathogen into the EU. Host availability and climate suitability factors occurring in parts of the EU are favourable for the further establishment of the pathogen. In the areas of its present distribution, including Italy, the pathogen has a direct impact on cultivated hosts. Phytosanitary measures are available to prevent the further introduction and spread of the pathogen into the EU. N. dimidiatum satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest.