Definition - What does Graft Incompatibility mean?
A graft incompatibility is the failure for a graft to create a strong union. The incompatibility results in unhealthy growth or inability for growth, which results in premature death of the graft. The reason for such results are due to incompatible and biological differences between the scion and the rootstock.
WineFrog explains Graft Incompatibility
When the graft partners the scion and the rootstock-have genetic differences, this is referred to as graft incompatibility. Without compatibility between the main rootstock and the graft (scion), healthy growth cannot occur. This is often a case with differential biochemical and cytological responses that occur at the early phase of grafting.
The success of a graft depends on the connections of vascular tissue, cellular compatibility, the formation of plasmodesmata and the existence or presence of growth regulators.