First report of ‘Candidatus Phytoplasma phoenicium’ in Italy
Up to now ‘Candidatus Phytoplasma phoenicium’ (EPPO A1 List) was currently known to occur only in Lebanon and in Iran. In spring 2017, symptoms resembling those of phytoplasmas were reported on 25% of 15-year-old almond plants (Prunus dulcis), cultivars Filippo Ceo and Genco grafted onto GF677, in a commercial orchard (20 ha) located in Grottaglie (Puglia region, southeast Italy). The development of many axillary buds with small and yellowish leaves, and witches’ brooms developing from the trunk, were the most frequent symptoms, followed by leaf rosetting, proliferation of slender shoots, tree decline, and dieback. Twenty-six leaf samples were collected in the symptomatic orchard, from both symptomatic (19) and asymptomatic (7) plants. Moreover, additional leaf samples (5) from asymptomatic almond orchards (comprising the same cultivars), located 80 km away from the infected fields at Valenzano (Province of Bari, Puglia), were also collected. Molecular analysis (PCR, nested-PCR, BLASTn, sequencing) identified ‘Ca. P. phoenicium’ in all the symptomatic and two of the seven asymptomatic plants from Grottaglie. Samples from Valenzano tested negative.
The situation of ‘Candidatus Phytoplasma phoenicium’ in Italy can be described as: Present, found in one orchard in southeast Italy (Puglia).
Sources
Nigro F, Sion V, Antelmi I, Choueiri E, Habib W, Bruno A, Boscia D (2020) First report of ‘Candidatus Phytoplasma phoenicium’ on almond in Southern Italy. Plant Disease 104(1),278. https://doi.org/10.1094/PDIS-01-19-0157-PDN