Situation of peach latent mosaic viroid in Campania (IT)
Surveys were carried out in peach orchards, in Campania (South of Italy), in order to study the incidence of peach latent mosaic viroid (EPPO A1 quarantine pest). This viroid induces a complex symptomatology: calico, yellow mosaic, discoloration of fruit skin, chlorosis, dieback or the disease may remain completely latent. Tests have been carried out on symptomatic and apparently healthy trees. Detection was performed by using polyacrylamide gel electrophoresis of the nucleic acid extracts and/or a molecular probe of the viroid (obtained from Spain). The results of this study showed that the viroid was constantly present in trees showing symptoms. In addition, the viroid was also detected in more than 50 % of apparently healthy trees. The observation of various symptoms and various electrophoretic profiles lead the authors to suppose that several strains could be present in the field. However, this hypothesis could not be verified in this study. It can be recalled that peach latent mosaic viroid had previously been reported in peach and nectarine orchards, in a well-defined area of Emilia-Romagna (Albanese et al., 1992). Peach latent mosaic viroid is also reported as present in France, Spain and Greece.
EPPO note: the relationships between the peach latent mosaic viroid observed in Europe and agents (probably also viroids) causing similar diseases in America (peach American mosaic) and in Asia (peach yellow mosaic) have not been clarified. Therefore in the meantime, EPPO still considers viroids causing peach mosaic in America and Asia as A1 quarantine pests. However, if similarities can be established between the European and the non-European viroids, the quarantine status of peach latent mosaic viroid will have to be revised.
Sources
Di Serio, F.; Ragozzino, A. (1995) [Investigation on the occurrence of the peach latent mosaic viroid (PLMVd) in peach trees in Campania].
Informatore Fitopatologico, no. 9, 57-61.
Albanese, G.; Giunchedi, L.; La Rosa, L.; Poggi Pollini, C. (1992) Peach latent mosaic viroid in Italy.
Acta Horticulturae, 309, 331-338.