June 24, 2009

Study finds plants can communicate

U.S. and Japanese scientists have discovered plants can communicate danger to their clones or genetically identical cuttings planted nearby.

University of California-Davis Professor Richard Karban and Kaori Shiojiri of Kyoto University found sagebrush responds to cues of self and non-self without physical contact.

Karban said the sagebrush communicated and cooperated with other branches of themselves to avoid being eaten by grasshoppers. The scientists said they suspect the plants warn their own kind of impending danger by emitting volatile cues, which might include secreting chemicals that deter herbivores or make the plant less profitable for herbivores to eat.

The findings mean plants are capable of more sophisticated behavior than we imagined, said Karban, who researches the interactions between herbivores (plant-eating organisms) and their host plants.

Plants are capable of responding to complex cues that involve multiple stimuli, Karban said. Plants not only respond to reliable cues in their environments, but also produce cues that communicate with other plants and with other organisms, such as pollinators, seed disperses, herbivores and enemies of those herbivores.

The study is reported in the journal Ecology Letters.