ARTICHOKE ITALIAN LATENT VIRUS CAUSES ARTICHOKE PATCHY CHLOROTIC STUNTING DISEASE

Artichoke patchy chlorotic stunting (APCS) is the most serious disease affecting artichoke in Greece. It is widespread in Argolis, the main artichoke centre in Greece, where the local thornless artichoke, cv. ' 'Argos'', is cultivated. The disease was first noticed in 1982, but to growers it was known since earlier times. Data collected during 1980- 1990 revealed its wide distribution in the area, its patchy dispersal in fields, and its annual radial increase of the patches during the ye ars, as well as a centripetal symptomatological severity gradient with in each patch. These observations indicated a soil-borne nature for th e disease. Field surveys for several viruses indicated a correlation o f APCS with artichoke Italian latent nepovirus (AILV), a soil-borne vi rus known to occur in such patches and transmitted by the vector nemat ode Longidorus fasciatus Roca et Lamberti. In experiments fulfilling K och's postulates, it was possible to reproduce the symptoms of APCS, d emonstrating that AILV is a cause of the disease, if not the only one. Field surveys also revealed the ubiquitous occurrence of artichoke mo ttled crinkle virus (AMCV), independently of any particular symptoms. In the same survey, broad bean wilt virus (BBWV), also, was recovered from artichoke in Greece for the first time.