SATELLITE-MEDIATED PROTECTION OF TOMATO AGAINST CUCUMBER MOSAIC-VIRUS .2. FIELD-TEST UNDER NATURAL EPIDEMIC CONDITIONS IN SOUTHERN ITALY

Tomato necrosis devastated the tomato crop in the Basilicata region of Italy in 1988. Several hundred tomato (Lycopersicon esculentum) seedlings representing the cultivars UC82B, Rutgers, Bandera, and Italpeel were preventively inoculated or "vaccinated" with cucumber mosaic virus (CMV) strain S containing the nonnecrogenic satellite S-CARNA 5 (CMV-associated RNA 5) and placed in a commercial tomato field in the Basilicata region of southern Italy to test for protection against tomato necrosis. When surveyed in July 1989, the protective effect of the vaccination was greater than 95%. The fruit yields from the protected plants were double those of the nonprotected controls. In the experimental field, the incidence of lethal necrosis in nonprotected control plants was 40%; however, in neighboring fields total destruction of the tomato crop occurred for the second consecutive year.