Journal Article

Changes in oak (Quercus robur) photosynthesis after winter moth (Operophtera brumata) herbivory are not explained by changes in chemical or structural leaf traits

Salinas, Norma, Gripenberg, Sofia, Riutta, Terhi, Salminen, Juha-Pekka, Malhi, Yadvinder, Visakorpi, Kristiina

2020

Overview

Insect herbivores have the potential to change both physical and chemical traits of their host plant. Although the impacts of herbivores on their hosts have been widely studied, experiments assessing changes in multiple leaf traits or functions simultaneously are still rare. We experimentally tested whether herbivory by winter moth (Operophtera brumata) caterpillars and mechanical leaf wounding changed leaf mass per area, leaf area, leaf carbon and nitrogen content, and the concentrations of 27 polyphenol compounds on oak (Quercus robur) leaves. To investigate how potential changes in the studied traits affect leaf functioning, we related the traits to the rates of leaf photosynthesis and respiration. Overall, we did not detect any clear effects of herbivory or mechanical leaf damage on the chemical or physical leaf traits, despite clear effect of herbivory on photosynthesis. Rather, the trait variation was primarily driven by variation between individual trees. Only leaf nitrogen content and a subset of the studied polyphenol compounds correlated with photosynthesis and leaf respiration. Our results suggest that in our study system, abiotic conditions related to the growth location, variation between tree individuals, and seasonal trends in plant physiology are more important than herbivory in determining the distribution and composition of leaf chemical and structural traits.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Animals / Biology and Life Sciences / Butterflies & moths / Carbon - metabolism / Caterpillars / Chemical composition / Chemical damage / Correlation analysis / Ecology and Environmental Sciences / Herbivores / Herbivory / Host plants / Host-Parasite Interactions / Insects / Larva - physiology / Leaf area / Leaves / Medicine and Health Sciences / Moths - growth & development / Moths - physiology / Nitrogen / Nitrogen - metabolism / Nitrogen content / Operophtera brumata / Organic chemistry / Photosynthesis / Plant growth / Plant Leaves - chemistry / Plant Leaves - metabolism / Plant Leaves - parasitology / Plant physiology / Plant Shoots - chemistry / Plant Shoots - metabolism / Polyphenols / Polyphenols - metabolism / Principal Component Analysis / Quercus - chemistry / Quercus - metabolism / Quercus - parasitology / Quercus robur / Respiration / Seasons / Stress, Mechanical / Variation / Winter / Wounding