Etiology of grape crown gall in Ontario

摘要

Crown gall was found mostly onviniferagrape (Vitis viniferaL.) cultivars in Ontario vineyards. The galls were usually small and aggregated along the trunk and cane; large woody galls were less common. Vines affected by crown gall died back in 3ndash;4 years after planting. All the nine strains ofAgrobacterium tumefaciens(Smith and Townsend) Conn isolated from galls corresponded to biotype 3 in determinative tests and were pathogenic onDatura, tobacco, tomato, and sunflower plants. Eight strains were sensitive to agrocin 84 on amended Stonier's medium. They were suppressed if inoculation was preceded 6ensp;h earlier byAgrobacterium radiobacterstrain K84 at wound sites onDaturaand tomato plants.