The debate over whether plants have feelings is about to be reopened with the publication of research by scientists in Italy and Germany.
Their findings suggest that plants under threat can marshal a positively devilish measure of cunning. Not only do they communicate the danger to plants nearby; they also call in help from other creatures.
Biologists at the University of Turin and the Max Planck Institute in Jena were on Monday reported to have found evidence that plants sensed — and reacted to — the presence of hungry, leaf-chomping grubs. Their response was to emit an odour similar to that of lavender.
This alerted other plants to the presence of a predator. But it also served to call in what modern military planners would term air support. Wasps, the natural enemies of grubs, were drawn by the odour to the plant where they either devoured the grub or injected it with eggs that later killed it.
The bulk of the three-year project was devoted to studying the Lima bean (Phaseolus lunatus), a native of central and south America.
But according to a report by the Italian daily La Repubblica the researchers elicited similar reactions from maize, from the plant that yields cranberry or borlotti beans (Phaseolus vulgaris) and from other species.
The detailed findings of their joint project are to be published in Plant Physiology, a review of the American Society of Plant Biologists.
Not the least intriguing question raised by the study is whether, at the start of the process they describe, there is something that can be termed fear. The debate began in 1966 when a lie detector expert, Cleve Backster, connected a plant to a polygraph. He said the machine registered changes as soon as he began to contemplate burning the plant’s leaves. – Guardian Unlimited Â