Title: | Induced responses to herbivory and jasmonate in three milkweed species |
Author(s): | Rasmann S; Johnson MD; Agrawal AA; |
Address: | "Department of Ecology and Evolutionary Biology, Cornell University, Corson Hall, Ithaca, NY 14853-2701, USA. sgr37@cornell.edu" |
DOI: | 10.1007/s10886-009-9719-0 |
ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
Abstract: | "We studied constitutive and induced defensive traits (latex exudation, cardenolides, proteases, and C/N ratio) and resistance to monarch caterpillars (Danaus plexippus) in three closely related milkweed species (Asclepias angustifolia, A. barjoniifolia and A. fascicularis). All traits showed significant induction in at least one of the species. Jasmonate application only partially mimicked the effect of monarch feeding. We found some correspondence between latex and cardenolide content and reduced larval growth. Larvae fed cut leaves of A. angustifolia grew better than larvae fed intact plants. Addition of the cardenolide digitoxin to cut leaves reduced larval growth but ouabain (at the same concentration) had no effect. We, thus, confirm that latex and cardenolides are major defenses in milkweeds, effective against a specialist herbivore. Other traits such as proteases and C/N ratio additionally may be integrated in the defense scheme of those plants. Induction seems to play an important role in plants that have an intermediate level of defense, and we advocate incorporating induction as an additional axis of the plant defense syndrome hypothesis" |
Keywords: | Animal Feed Animals Asclepias/*drug effects/metabolism/*physiology Cardenolides/metabolism Cyclopentanes/*pharmacology Larva/growth & development/physiology Latex/metabolism Lepidoptera/growth & development/*physiology Oxylipins/*pharmacology Peptide Hydr; |
Notes: | "MedlineRasmann, Sergio Johnson, M Daisy Agrawal, Anurag A eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2009/12/17 J Chem Ecol. 2009 Nov; 35(11):1326-34. doi: 10.1007/s10886-009-9719-0. Epub 2009 Dec 11" |