Virus Diseases Infecting Almond Germplasm in Lebanon

Cultivated and wild almond species were surveyed for virus diseases. Four viruses infected cultivated almonds (Prunus dulcis): Prunus necrotic ringspot virus (PNRSV), Prune dwarf virus (PDV), Apple chlorotic leaf spot virus (ACLSV) and Apple mosaic virus (ApMV). Only ACLSV and ApMV were detected on wild almonds, (Prunus orientalis and P. korschinskii). The occurence of PNRSV or PDV on seeds used for the production of rootstocks, on seedlings in nurseries, and on mother plants revealed the need for a certification program. There was no evidence for the occurrence of Plum pox virus (PPV) or Tomato ringspot virus (ToRS)