Journal of Chemical Ecology

, Volume 19, Issue 3, pp 411–425

An elicitor in caterpillar oral secretions that induces corn seedlings to emit chemical signals attractive to parasitic wasps

  • Ted C. J. Turlings
  • Philip J. McCall
  • Hans T. Alborn
  • James H. Tumlinson
Article

DOI: 10.1007/BF00994314

Cite this article as:
Turlings, T.C.J., McCall, P.J., Alborn, H.T. et al. J Chem Ecol (1993) 19: 411. doi:10.1007/BF00994314

Abstract

Regurgitate of corn-fed beet armyworm (BAW) caterpillars,Spodoptera exigua, when applied to damaged sites of corn (Zea mays) seedlings, causes the release of relatively large amounts of terpenes by the seedlings several hours later. This plant response could be induced by merely placing the cut stem of seedlings in a solution of BAW regurgitate for 12 hr, a response that could not be induced by placing seedlings in water only. Regurgitate of BAW fed various diets, including a minimal diet of filter paper, were all active. However, seedlings placed in corn leaf juice, BAW hemolymph, or BAW feces extract released significantly smaller amounts of terpenes than did seedlings placed in BAW regurgitate. These results indicate that the active components are present in relatively large concentrations in regurgitate and that they are not related to the food source. Furthermore, regurgitate from several other species of caterpillars (Spodoptera frugiperda, Helicoverpa zea,Trichoplusia ni, andAnticarsia gemmatalis) as well as from the grasshopperSchistocerca americana induced the release of significant amounts of terpenes in corn seedlings. The release of these volatiles, therefore, appears to be a general response to attack by phytophagous insects. The terpene-releasing corn seedlings were highly attractive to the generalist parasitoidCotesia marginiventris and to the specialized parasitoidMicroplitis croceipes. This study confirms a systemic herbivore-elicited release of terpenes in corn. It is proposed that such chemicals serve multifunctional purposes that directly and indirectly protect plants against herbivorous arthropods and pathogens.

Key Words

ElicitorcornZea mayscaterpillar regurgitateplant volatilessynomonessemiochemicalsparasitoidsCotesia marginiventrisMicroplitis croceipeshost searching

Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • Ted C. J. Turlings
    • 3
  • Philip J. McCall
    • 3
  • Hans T. Alborn
    • 3
  • James H. Tumlinson
    • 3
  1. 1.Biomedical Science DivisionLiverpool School of Tropical MedicineLiverpoolUK
  2. 2.Department of Chemical EcologyUniversity of GöteborgGöteborgSweden
  3. 3.Insect Attractants, Behavior, and Basic Biology Research Laboratory Agricultural Research ServiceU.S. Department of AgricultureGainesville