Publication details.


Author(s):G. Hernan, I. Castejon-Silvo, J. Terrados, F. Tomas
Title:Herbivory and resource availability shift plant defense and herbivore feeding choice in a seagrass system
JCR Impact Factor:2.654
Issue No.:3
Abstract:Numerous hypotheses have been posited to explain the observed variation in plant defense strategies against herbivory. Under
resource-rich environments, plants are predicted to increase their tolerance (limiting resource model; LRM) and, while the
resource availability hypothesis (RAH) predicts a decrease in constitutive resistance in plant species growing in resource-rich
environments, at the intraspecific level, plants are predicted to follow an opposite pattern (intraspecific RAH). Furthermore,
the effect of multiple factors in modulating plant defense strategies has been scarcely explored and is more difficult to predict.
Our aim was to understand how plant defense traits respond to herbivory, resource availability and their interactions, and to
assess the effects on plant palatability. To this end, we performed an in situ factorial experiment at two sites simulating three
herbivory levels and two nutrient availability conditions with the seagrass Posidonia oceanica. Additionally, we performed a
series of feeding experiments with its two main herbivores. While plants decreased their constitutive resistance under nutrient
fertilization (contrary to intraspecific RAH but in accordance to the RAH), and did not increase allocation to tolerance
(likely due to resource limitation, LRM), simulated herbivory induced resistance traits. However, we found no interactive
effects of nutrient fertilization and herbivory simulation on plant defense. Both herbivores responded similarly to changes
in plant palatability, strongly preferring nutrient-enriched plants and non-clipped plants. This work highlights the need to
better understand the drivers of plant defense intraspecific variability in response to resources, particularly in habitat-forming
species where changes in plant traits and abundance will cascade onto associated species.

Related staff

  • Gema Hernan Martinez
  • Fiona Tomas Nash
  • Inés Castejón Silvo
  • Jorge Terrados Muñoz
  • Related departments

  • Marine Ecology
  • Related projects