Title: | Abiotic induction affects the costs and benefits of inducible herbivore defenses in Datura wrightii |
Author(s): | Kruidhof HM; Allison JD; Hare JD; |
Address: | "Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6700 Wageningen, The Netherlands" |
DOI: | 10.1007/s10886-012-0168-9 |
ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
Abstract: | "We evaluated the costs and benefits of continuous high-level expression of defenses relative to naturally-induced defenses in field-grown Datura wrightii in the presence and absence of herbivores. We induced D. wrightii plants with monthly applications of the plant hormone methyl jasmonate (MeJA) and assessed levels of inducible proteinase inhibitors (Pins). MeJA application increased Pin production by 124 %, whereas the increase in Pins due to herbivory was more modest (36 %). Pin induction was costly and significantly reduced plant fitness compared to unmanipulated plants both in the presence and absence of herbivores. Although MeJA-treated plants exposed to herbivory suffered significantly less herbivore damage than unmanipulated plants exposed to herbivory, this was not accompanied by a corresponding fitness benefit. In contrast to glasshouse studies in which protected plants never expressed Pins, Pin induction occurred in field-grown plants not treated with MeJA and completely protected from herbivory. Subsequent experiments confirmed that putative herbivore defenses can be induced abiotically in D. wrightii as: 1) Pin levels did not differ significantly between field-grown plants protected from herbivory and plants exposed to chronic herbivory over the full season; and 2) plants exposed to ambient UV-B light in the absence of herbivory expressed low levels of Pins after two wk of exposure, whereas plants protected from UV-B remained uninduced. The costs of induced responses may be relatively easily determined under field conditions, but there may be many inducing agents in the field, and the benefits of induction may be difficult to associate with any single inducing agent" |
Keywords: | Acetates/*metabolism Animals California Cyclopentanes/*metabolism Datura/growth & development/*physiology Food Chain Genetic Fitness *Herbivory Insecta/physiology Oxylipins/*metabolism Plant Growth Regulators/*metabolism Protease Inhibitors/metabolism Ult; |
Notes: | "MedlineKruidhof, H M Allison, Jeremy D Hare, J Daniel eng Research Support, U.S. Gov't, Non-P.H.S. 2012/08/31 J Chem Ecol. 2012 Oct; 38(10):1215-24. doi: 10.1007/s10886-012-0168-9. Epub 2012 Jul 28" |