Quorum-sensing signal production by Agrobacterium vitis strains and their tumor-inducing and tartrate-catabolic plasmids.

Agrobacterium vitis strains, their tumor-inducing (pTi) and tartrate utilization (pTr) plasmid transconjugants and grapevine tumors were analyzed for the presence of N-acyl-homoserine lactones (AHLs). All wild-type A. vitis strains produced long-chain signals.