Pest categorisation of small-spored Alternaria carrying the genes for the AM- or AK-toxin biosynthesis

Alternaria alternata, Alternaria leaf blotch, black spot of pears, impacts, Malusspp., pestdistribution, Pyrusspp.
First published in the EFSA Journal
20 December 2017
22 November 2017
Scientific Opinion

The Panel on Plant Health performed a pest categorisation of small-spored Alternaria carrying the genes for the AM- or AK-toxin biosynthesis, for the EU. The identity of the pests is clearly defined and reliable methods exist for their detection/identification. They are listed in Annex IIAI of Directive 2000/29/EC as Alternaria alternata (non-European pathogenic isolates). Their distribution in the EU is restricted though with some uncertainty. The AM-toxin producer Alternaria affect Malus spp. and Pyrus communis (European pear), whereas the AK-toxin producer affect Pyrus pyrifolia, Pyrus bretschneideri and Pyrus ussuriensis (Asian pears). The pests could potentially enter the EU on host-planting material and fruit originating in infested countries. There are no biotic/abiotic factors limiting their potential establishment and spread in the EU, as their epidemiology is similar to that of other well-established Alternaria spp. Apples and European pears are widespread in the EU; Japanese pears are also present, but no data was found on their abundance/distribution. In the infested areas, the pests cause premature defoliation, fruit spotting and rot resulting in yield/quality losses. It is expected that the introduction and spread of the pests in the EU could impact apple and pear production, although the magnitude is unknown. Cultural practices and chemical measures may reduce the inoculum and the disease, but they cannot eliminate the pests. Phytosanitary measures are available to mitigate the risk of introduction and spread of the pests. The pests do not meet all the criteria assessed by EFSA for consideration as potential Union quarantine pests, as they are not under official control in those EU restricted areas where they have been found. The pests do not meet all the criteria assessed by EFSA to consider them as Union regulated non-quarantine pests, as host plants for planting are not the main means of pest spread.

Panel members at the time of adoption
Claude Bragard, David Caffier, Thierry Candresse, Elisavet Chatzivassiliou, Katharina Dehnen-Schmutz, Gianni Gilioli, Jean-Claude Grégoire, Josep Anton Jaques Miret, Michael Jeger, Alan MacLeod, Maria Navajas Navarro, Björn Niere, Stephen Parnell, Roel Potting, Trond Rafoss, Vittorio Rossi, Gregor Urek, Ariena Van Bruggen, Wopke Van der Werf, Jonathan West and Stephan Winter.
Panel on Plant Health
alpha [at]
EFSA Journal 2017;15(12):5099
Question Number
On request from
European Commission