Ref ID: 8921
Ref Type: Journal
Authors: Close, D. C. and McArthur, C.
Pub Date: 2002
Journal Name: Oikos
Volume: 99
Issue: 1
Start Page: 166
End Page: 172
ISBN/ISSN:
Keywords: balance/damage/defence/ecological/environment/evolution/growth/herbivore/interaction/leaf/light/metabolite/nutrient/paper/phenolics/plant/plant metabolites/potential/protection/resource/risk/secondary metabolite/species/variation
Abstract: Plant phenolics have been considered classic defence compounds for protection from herbivores, ever since plant secondary metabolites were suggested to have evolved for that reason. The resource availability and carbon-nutrient balance hypotheses proposed that variation in phenolic levels between and within plant species reflects environmental availability of nutrients and light, and represents a trade-off in allocation by plants to growth and defence against herbivores. In contrast to these concepts, we suggest that (1) the main role of many plant phenolics may be to protect leaves from photodamage, not herbivores; (2) they can achieve this by acting as antioxidants; and (3) their levels vary with environmental conditions in order to counteract this potential photodamage. We therefore suggest that patterns in phenolic levels, often used to support the concept of trade-off between growth and herbivore defence in relation to resource availability, may actually reflect different risks of photodamage. We suggest that the level of many phenolics is low under some environmental conditions, not because resources to produce them are limited, but simply because the risk of photodamage is low and they are not required. If our photodamage hypothesis is correct, a reassessment of the ecological and evolutionary role of many phenolics in plant defence theory is required
Notes: Entered by Dugs (7/6/2001): Edited by Hugh (28/5/03)
Reprint: Not in File
Program: SPF Sustainable Management
Project: C3
Deliverable: C3-2
Confidentiality: Public
Availability: Authors
Report: Annual Report 2002/3
Type: Article