Skip to main content
Research article - Peer-reviewed, 2010

Growth and chemical defense in willow seedlings: trade-offs are transient

Orians, Colin Mark; Hochwender, Cris G.; Fritz, Robert S.; Snall, Tord


Many studies have failed to detect costs of defense and some have even found a positive correlation between growth and the concentrations of chemical defenses. These studies contradict the theoretical assumption that anti-herbivore defenses are costly-produced at the expense of growth and/or reproduction. Costs, however, may be transient and therefore difficult to detect. Here we tested the hypothesis that costs of defense would be pronounced early in development when root growth is prioritized (high percent root allocation), but not later in development. To test this hypothesis, we grew F(2) hybrid willow seedlings from five different families, and harvested cohorts of even-aged seedlings after 6, 7, 8 and 9 weeks of growth. Seedlings were divided into root and shoot tissue and shoots were analyzed for phenolics (condensed tannins and phenolic glycosides). We found evidence for transient costs of defense. The concentrations of phenolics were negatively correlated with total biomass, shoot biomass, and the proportion of biomass allocated to roots in week 6. After week 6, however, the concentrations of phenolics were positively correlated with shoot biomass and total biomass, while phenolics were uncorrelated with the proportion of biomass allocated to roots. These results, the first ever, to our knowledge, with woody plants, suggest that costs of defense were transient; specifically, costs were found in early development, when root establishment was a priority. Our findings suggest that studies should focus more on trade-offs early in plant development.


Cost of defense; F(2) hybrids; Phenolics; Relative root allocation; Salix

Published in

2010, Volume: 163, number: 2, pages: 283-290

    SLU Authors

    UKÄ Subject classification

    Environmental Sciences related to Agriculture and Land-use

    Publication Identifiers


    Permanent link to this page (URI)