Title: | Changes in clonal poplar leaf chemistry caused by stem galls alter herbivory and leaf litter decomposition |
Author(s): | Kunkler N; Brandl R; Brandle M; |
Address: | "Department of Ecology - Animal Ecology, Faculty of Biology, Philipps-Universitat Marburg, Marburg, Germany" |
DOI: | 10.1371/journal.pone.0079994 |
ISSN/ISBN: | 1932-6203 (Electronic) 1932-6203 (Linking) |
Abstract: | "Gall-inducing insects are highly specialized herbivores that modify the phenotype of their host plants. Beyond the direct manipulation of plant morphology and physiology in the immediate environment of the gall, there is also evidence of plant-mediated effects of gall-inducing insects on other species of the assemblages and ecosystem processes associated with the host plant. We analysed the impact of gall infestation by the aphid Pemphigus spirothecae on chemical leaf traits of clonal Lombardy poplars (Populus nigra var. italica) and the subsequent effects on intensity of herbivory and decomposition of leaves across five sites. We measured the herbivory of two feeding guilds: leaf-chewing insects that feed on the blade (e.g. caterpillars and sawfly larvae) and skeletonising insects that feed on the mesophyll of the leaves (e.g. larvae of beetles). Galled leaves had higher phenol (35%) and lower nitrogen and cholorophyll contents (35% respectively 37%) than non-galled leaves, and these differences were stronger in August than in June. Total herbivory intensity was 27% higher on galled than on non-galled leaves; damage by leaf chewers was on average 61% higher on gall infested leaves, whereas damage by skeletonising insects was on average 39% higher on non-galled leaves. After nine months the decomposition rate of galled leaf litter was 15% lower than that of non-galled leaf litter presumably because of the lower nitrogen content of the galled leaf litter. This indicated after-life effects of gall infestation on the decomposers. We found no evidence for galling x environment interactions" |
Keywords: | Animals Ecosystem Environment Feeding Behavior/*physiology Herbivory/*physiology Insecta/metabolism/physiology Nitrogen/metabolism Plant Leaves/metabolism/*physiology Plant Stems/metabolism/*physiology Populus/metabolism/*physiology; |
Notes: | "MedlineKunkler, Nora Brandl, Roland Brandle, Martin eng 2013/11/22 PLoS One. 2013 Nov 19; 8(11):e79994. doi: 10.1371/journal.pone.0079994. eCollection 2013" |