DO PLANTS TAP SOS SIGNALS FROM THEIR INFESTED NEIGHBORS

Ecologists have not been able to show unambiguous evidence for the inv olvement of plant-to-plant signal transfer in the defence strategies o f plants. However, phytopathologists and plant physiologists recently demonstrated that resistance in undamaged plants can be elicited by vo latiles of plant origin. Now that empirical evidence is accumulating, there is every reason to ask why plants use the available information on the infestation status of their neighbours and to assess the fitnes s advantages associated with the tuning of their defence. The debate o n the ecological and evolutionary significance of interplant communica tion needs to be revived.