Plant-plant communication and community of herbivores on tall goldenrod

The volatiles from damaged plants induce defense in neighboring plants. The phenomenon is called plant-plant communication, plant talk, or plant eavesdropping. Plant-plant communication has been reported to be stronger between kin plants than genetically far plants in sagebrush. Why do plants distinguish volatiles from kin or genetically far plants? We hypothesize that plants respond only to important conditions; the induced defense is not free of cost for the plant. To clarify the hypothesis, we conducted experiments and investigations using goldenrod of four different genotypes. The arthropod community on tall goldenrods were different among four genotypes. The response to volatiles was stronger from genetically close plants to the emitter than from genetically distant plants from the emitter. The volatiles from each genotype of goldenrods were different; and they were categorized accordingly. Moreover, the arthropod community on each genotype of goldenrods were different. Synthesis: Our results support the hypothesis: Goldenrods respond to volatiles from genetically close plants because they would have similar arthropod species. These results are important clues elucidating adaptive significance of plant-plant communication.

Automated summary

The volatiles released by damaged plants can trigger defense responses in neighboring plants. This phenomenon, known as plant-plant communication or eavesdropping, is stronger between kin plants in certain environments. Plants may distinguish volatiles from kin plants to respond to important conditions and minimize the cost of induced defense. Experiments with goldenrods of different genotypes revealed that plants respond stronger to volatiles from genetically close plants, likely due to similar arthropod communities. These findings provide important insights into the adaptive significance of plant-plant communication.