First reports of Colletotrichum fructicola in the EPPO region (France and Italy)
Bitter rot is one of the prevalent diseases of apple (Malus domestica) worldwide. The disease affects the fruit preharvest in orchards and/or postharvest in storage, resulting in considerable economic losses. Until recently the reported causal agents in Europe belonged to the Colletotrichum acutatum species complex; however, Colletotrichum fructicola, belonging to the C. gloeosporioides species complex, is known to cause bitter rot of apple in the USA, the Republic of Korea, Brazil, and Uruguay. In September 2017, bitter rot symptoms were observed on apple fruit (cultivars Joya Cripps Red, Granny Smith, and Pink Lady) in four orchards in the region of Occitanie in France. The pathogen was identified as C. fructicola.
C. fructicola was also identified as the cause of a severe outbreak of fruit rot in commercial ‘Pink Lady’ apple orchards (>20 ha in total) in the region Emilia-Romagna (Northern Italy) in late summer 2019. C. fructicola has a wide host range worldwide and it has also been identified on other plants in Italy, e.g. avocado (Persea americana), aromatic and ornamental plants.
A distribution map can be viewed on the EPPO Global Database: https://gd.eppo.int/taxon/COLLFC/distribution.
In 2021, EFSA conducted a pest categorization and concluded that the pathogen is likely to establish and cause negative impacts in the European Union. However there is uncertainty on the current distribution because of the re-evaluation of Colletotrichum taxonomy. Systematic surveys would be useful to know which Colletotrichum species are currently present in European orchards.
Sources
EPPO (2016) Mini datasheet on Colletotrichum fructicola (Ascomycota) prepared during the DROPSA project. Available at https://gd.eppo.int/taxon/COLLFC/documents
EFSA PLH Panel (EFSA Panel on Plant Health), Bragard C, Dehnen-Schmutz K, Di Serio F, Gonthier P, Jacques M-A, Jaques Miret JA, Justesen AF, MacLeod A, Magnusson CS, Milonas P, Navas-Cortes JA, Parnell S, Potting R, Thulke H-H, Van der Werf W, Civera AV, Yuen J, Zappala L, Migheli Q, Vloutoglou I, Campese C, Maiorano A, Streissl F, Reignault PL (2021) Scientific Opinion on the pest categorisation of Colletotrichum fructicola. EFSA Journal 19(8), 6803, 41 pp. https://doi.org/10.2903/j.efsa.2021.6803
Guarnaccia V, Martino I, Gilardi G, Garibaldi A and Gullino ML (2021) Colletotrichum spp. causing anthracnose on ornamental plants in Northern Italy. Journal of Plant Pathology 103, 127–137.
Nodet P, Chalopin M, Crété X, Baroncelli R, Le Floch G (2019) First report of Colletotrichum fructicola causing apple bitter rot in Europe. Plant Disease 103(7), 1767.
Wenneker M, Pham KT, Kerkhof E, Harteveld DO (2021) First report of preharvest fruit rot of ‘Pink Lady’ apples caused by Colletotrichum fructicola in Italy. Plant Disease 105(5), 1561.