First report of Lecanosticta acicola on Atlas cedar (Cedrus atlantica)
Lecanosticta acicola (EPPO A2 List) is the causal agent of brown spot needle blight on Pinus trees. In France it was first recorded in 1993 and it is mainly present in South-Western parts of the country. In spring 2020, light to severe defoliation and severe reddening of the attached needles, starting from the lower parts of the tree, were observed on twigs of adult Atlas cedar (Cedrus atlantica) planted in 1998 in a forest in the Tarn-et-Garonne department (Occitanie region, South-Western France). About 50% of the cedar trees in the plot showed these symptoms but no mortality was observed. L. acicola was identified by morphological and molecular methods (PCR, sequencing).
This is the first record of L. acicola on C. atlantica worldwide, and the first record on a non-pine host in the European Union. In 2018, L. acicola had been detected for the first time on a non-pine host in an arboretum in Turkey on a Lebanon cedar (Cedrus libani) (EPPO RS 2021/064).
In autumn 2021, L. acicola was detected again on C. atlantica, in the Dordogne and Gers departments (Nouvelle-Aquitaine region, South-Western France). L. acicola was not detected in Pinus spp. despite intensive inspections of pine trees growing close to the affected cedars.
Atlas cedar trees have been being planted in Southern France to adapt forests to climate change. In the European Union, L. acicola has been a Regulated Non-Quarantine Pest since 2019 and measures only applies to plants for planting (except seeds) of Pinus spp.
Sources
Schenck N, Renault C, Saurat C, Daubree JB, Kersaudy E, Husson C, Ioos R (2022) First report of Lecanosticta acicola causing brown spot needle blight on Atlas cedar in France. New Disease Reports 45(2), e12082. https://doi.org/10.1002/ndr2.12082
EU (2019) Commission Implementing Regulation (EU) 2019/2072 of 28 November 2019 establishing uniform conditions for the implementation of Regulation (EU) 2016/2031 of the European Parliament and the Council, as regards protective measures against pests of plants, and repealing Commission Regulation (EC) No 690/2008 and amending Commission Implementing Regulation (EU) 2018/2019 (OJ L 319, 10.12.2019, p. 1). Consolidated version available at http://data.europa.eu/eli/reg_impl/2019/2072/2022-04-11