Field assessment and diagnostic methods for detection of grapevine viruses.

The diagnosis of grapevine viral diseases and their associated viruses is usually performed by visual observation of symptoms or by using laboratory tests. The observation of symptoms can be carried out directly in the field, in case of manifest pathologies, or by means of biological indexing with susceptible indicators, in case of latent diseases. The laboratory assays include various serological and biomolecular tests, based on the detection of viral capsid and nucleic acid, respectively. Serological assays are largely used, also thanks to the availability of commercial kits. Biomolecular assays underwent a dramatic evolution in the last years, from dot-blot hybridisation to various PCRbased techniques and finally to microarrays, improving their sensitivity and reliability