Journal Article

Systemic release of chemical signals by herbivore-injured corn

Turlings, T.C.J. (Insect Attractants, Behavior, and Basic Biology Research Laboratory, ARS, USDA, Gainesville, FL), Tumlinson, J.H

1992

Overview

Corn seedlings respond to insect herbivore-inflicted injury by releasing relatively large amounts of several characteristic terpenoids and, as a result, become highly attractive to parasitic wasps that attack the herbivores. Chemical evidence showed that the induced emission of volatiles is not limited to the sites of damage but occurs throughout the plant. This evidence was obtained by comparing the release of volatiles from leaves of unharmed (control) seedlings with the release of volatiles from undamaged leaves of seedlings with two injured leaves treated with caterpillar regurgitant. Immediately after injury no differences were measured in the released volatiles, but several hours later the undamaged leaves of injured plants released the terpenoids linalool, (3E)-4,8-dimethyl-1,3,7-nonatriene, and (3E,7E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene in significantly larger amounts than leaves of unharmed plants. Other volatiles that are released by herbivore-injured leaves were detected occasionally only in trace amounts from the undamaged leaves of a damaged seedling. The systemic release of volatiles by injured corn coincided with attractiveness to the parasitoid Cotesia marginiventris; undamaged leaves of injured plants became significantly more attractive than leaves from control seedlings. These findings show conclusively that when a plant is injured by an insect herbivore the whole plant emits chemical signals.

• Publisher: National Academy of Sciences of the United States of America,National Academy of Sciences
• Subject: APANTELES / Biological and medical sciences / Botany / Braconidae / Chemical hazards / COMPOSE VOLATIL / COMPUESTO VOLATIL / Corn / Cotesia marginiventris / crop damage / Dams / DEPREDADORES / FLORIDA / FLORIDE / Flowers & plants / Fundamental and applied biological sciences. Psychology / Herbivores / Hymenoptera / Infestation / Insect behavior / insect pests / INSECTE NUISIBLE / INSECTOS DANINOS / Leaves / PARASITE / parasites / Parasitism / Parasitism and symbiosis / Parasitoids / PARASITOS / PERDIDAS DE LA COSECHA / PERTE DE RECOLTE / PHYTOSEIULUS PERSIMILIS / Plant physiology and development / PLANTULAS / PLANTULE / PREDATEUR / predators / Seedlings / SPODOPTERA EXIGUA / TERPENOIDE / TERPENOIDOS / Terpenoids / TETRANYCHUS URTICAE / volatile compounds / ZEA MAYS