Transmission by cicadellids of Corsican vine yellowing. Identification of this disease with golden flavescence. 1. - Tests carried out outside Corsica.
The results are presented of studies that indicated that the yellows disease affecting grapevines in Corsica is identical with the golden flavescence disease described from Armagnac, France. The causal agent of the Corsican disease was transmitted from grapevine to grapevine and from grapevine to broad bean (Vicia faba) (and vice versa) by Scaphoideus titanus Ball (littoralis Ball), the main vector of golden flavescence, and from broad bean to broad bean by Euscelidius variegatus (Kirschb.), another vector of golden flavescence. The latter cicadellid had no diapause and is therefore useful for year-round maintenance of the pathogen in the laboratory. It was found necessary to use whole diseased plants transplanted in the year when symptoms first appeared as sources of infection for the leafhoppers; cuttings from diseased plants were not suitable for this purpose.