Leaf trichome responses to herbivory in willows: induction, relaxation and costs
Article first published online: 9 APR 2008
© The Authors (2008). Journal compilation © New Phytologist (2008)
Volume 179, Issue 1, pages 176–184, July 2008
How to Cite
Björkman, C., Dalin, P. and Ahrné, K. (2008), Leaf trichome responses to herbivory in willows: induction, relaxation and costs. New Phytologist, 179: 176–184. doi: 10.1111/j.1469-8137.2008.02442.x
- Issue published online: 9 APR 2008
- Article first published online: 9 APR 2008
- Received: 25 September 2007; Accepted: 15 February 2008
- induced plant defence;
- insect herbivory;
- leaf trichomes;
- Salix cinerea;
- • To circumvent the inherent problem of discriminating between the cost of losing photosynthetic tissue and the cost of producing an inducible defence, the growth response of herbivore-damaged plants was compared with plants damaged mechanically to the same extent but without eliciting the defence.
- • Two experiments were conducted, studying the response of willows (Salix cinerea) to damage by adult leaf beetles (Phratora vulgatissima).
- • In the first experiment, willows produced new leaves with an enhanced leaf trichome density 10–20 d after damage, coinciding in time with the feeding of beetle offspring. The response was relaxed in foliage produced 30–40 d after damage. In the second experiment, which also included mechanical damage, willows exposed to beetle feeding showed an increase in leaf trichome density of the same magnitude (> 70%) as in the first experiment. The cost of producing the defence was a 20% reduction in shoot length growth and biomass production. Willows exposed to mechanical damage had an 8% reduction in shoot length growth compared with control plants, that is, a cost of leaf area removal.
- • The results are the first quantitative estimates of the cost of a plant defence induced by natural and low amounts (3.3%) of herbivory.