Elevated CO2 interacts with herbivory to alter chlorophyll fluorescence and leaf temperature in Betula papyrifera and Populus tremuloides

Abstract

Herbivory can influence ecosystem productivity, but recent evidence suggests that damage by herbivores modulates potential productivity specific to damage type. Because productivity is linked to photosynthesis at the leaf level, which in turn is influenced by atmospheric CO(2) concentrations, we investigated how different herbivore damage types alter component processes of photosynthesis under ambient and elevated atmospheric CO(2). We examined spatial patterns in chlorophyll fluorescence and the temperature of leaves damaged by leaf-chewing, gall-forming, and leaf-folding insects in aspen trees as well as by leaf-chewing insects in birch trees under ambient and elevated CO(2) at the aspen free-air CO(2) enrichment (FACE) site in Wisconsin. Both defoliation and gall damage suppressed the operating efficiency of photosystem II (ΦPSII) in remaining leaf tissue, and the distance that damage propagated into visibly undamaged tissue was marginally attenuated under elevated CO(2). Elevated CO(2) increased leaf temperatures, which reduced the cooling effect of gall formation and freshly chewed leaf tissue. These results provide mechanistic insight into how different damage types influence the remaining, visibly undamaged leaf tissue, and suggest that elevated CO(2) may reduce the effects of herbivory on the primary photochemistry controlling photosynthesis.

Herbivore induction of jasmonic acid and chemical defences reduce photosynthesis in Nicotiana attenuata

“…We observed reduced electron transport efficiency in more remaining leaf tissue of wild-type than asLOX plants, but small reductions around chewed leaf edges in asLOX plants immediately after insect attack were evident. This result is consistent with previous data for N. attenuata (Halitschke et al ., 2011) and surveys of chewing herbivore damage in other species (Aldea et al ., 2006; Barron-Gafford et al ., 2012; Nabity et al ., 2012). Given that damage was propagated in both genotypes, feeding interrupted electron transport by physically disrupting tissues leading to desiccation, or by introducing electron scavengers through insect oral secretions or lysed cells (e.g.…”

“…Welter, 1989). Tissues adjacent to feeding damage also may exhibit reduced photosynthesis, further contributing to reductions in productivity (Aldea et al ., 2006; Nabity et al ., 2009, 2012). Feeding elicits the production of a complex network of hormone signalling that induces defences and initiates the trade-off between using resources for growth or defence.…”

“…When caterpillar feeding removed 5% of the leaf area of wild parsnip ( Pastinaca sativa L.), photosynthesis declined by 20% in the remaining foliage for at least 3 d as a result of ruptured oil tubes containing autotoxic terpenes (Zangerl et al ., 2002; Gog et al ., 2005). Defoliation in other species that lack autotoxic defences also reduces photosynthesis (Aldea et al ., 2005, 2006; Nabity et al ., 2012). In some cases, the loss of photosynthesis in remaining tissue can equal the amount of tissue consumed, effectively doubling fitness costs for each bite consumed (Aldea et al ., 2006).…”

Permafrost‐driven differences in habitat quality determine plant response to gall‐inducing mite herbivory

“…Florentine, Raman & Dhileepan ; Zvereva, Lanta & Kozlov ; Patankar, Thomas & Smith ; Nabity et al . ). There is increasing evidence that gall formation causes disruption beyond simple stomatal down‐regulation, and in fact has significant negative impacts on photosystem II quantum efficiency (Aldea et al .…”

“…However, a recent and growing body of literature seems to suggest that galling for the most part causes significant declines in photosynthesis (e.g. Florentine, Raman & Dhileepan 2005;Zvereva, Lanta & Kozlov 2010;Patankar, Thomas & Smith 2011;Nabity et al 2012). There is increasing evidence that gall formation causes disruption beyond simple stomatal downregulation, and in fact has significant negative impacts on photosystem II quantum efficiency (Aldea et al 2006;Huang et al 2011), along with modifications to photosynthetic pigments (Yang et al 2003;Gailite, Andersone & Ievinsh 2005;Samsone, Andersone & Ievinsh 2012) and carbon metabolites (Chakrabarti, Chakrabarti & Chakrabarti 2011;Patankar et al 2013).…”