Resistance of Grape Rootstocks to Crown Gall 1996-1997

Crown gall can develop on grapevines wounded by freezing temperatures, mechanical damage or\ud grafting. Increased demand for grape varieties grafted to phylloxera resistant rootstocks has led to\ud increased incidence of crown gall at graft unions. Therefore a search for plant material that is resistant to\ud crown gall has been undertaken. Previous studies on resistance have produced confusing and in some\ud cases contradictory results, probably due to the difference in methods and agrobacterial strains used in\ud each investigation (5, 11)