Thermal acclimation of respiration but not photosynthesis in Pinus radiata

Abstract

Pinus radiata L. were grown in climate-controlled cabinets under three night/day temperature treatments, and transferred between treatments to mimic changes in growth temperature. The objective was to determine the extent to which dark respiration and photosynthesis in pre-existing and new needles acclimate to changes in growth temperatures. We also assessed whether needle nitrogen influenced the potential for photosynthetic and respiratory acclimation, and further assessed if short-term (instantaneous, measured over a few hours) respiratory responses are accurate predictors of long-term (acclimated, achieved in days--weeks) responses of respiration to changing temperature. Results show that respiration displayed considerable potential for acclimation. Cold and warm transfers resulted in some acclimation of respiration in preexisting needles, but full acclimation was displayed only in new needles formed at the new growth temperature. Short-term respiratory responses were poor predictors of the long-term response of respiration due to acclimation. There was no evidence that photosynthesis in pre-existing or new needles acclimated to changes in growth temperature. N status of leaves had little impact on the extent of acclimation. Collectively, our results indicate that there is little likelihood that respiration would be significantly stimulated in this species as night temperatures increase over the range of 10--20 C, but that inclusion of temperature acclimation of respiration would in fact lead to a shift in the balance between photosynthesis and respiration in favour of carbon uptake.

The contribution of respiration in tree stems to the Dole Effect

“…For example, we found the highest discrimination in the Apple tree shortly after bud burst, which somewhat resembles the high discrimination reported for aquatic systems shortly after spring bloom (Luz and Barkan, 2011). These findings are in agreement with findings of increased AOX activity shortly after changes in environmental conditions, or before an increase in the rates of respiration through the COX (Moore et al, 2002;Rachmilevitch et al, 2007). As noted above, the AOX is also reported to be activated as a response to stress.…”

“…To the best of our knowledge, this study is the only one to date that has estimated AOX activity in intact plants in the field. Given the known relation between AOX and various types of stress (Vanlerberghe and McIntosh, 1997;Moore et al, 2002;Rachmilevitch et al, 2007), working with intact plants has a clear advantage over incubating desiccated plant tissue (Ow et al, 2008;Searle and Turnbull, 2011) that might exhibit a wound response. Using the approach demonstrated here, it is possible to trace how the AOX contribution in woody tissue of a single plant changes seasonally, and due to environmental conditions such as temperature and soil moisture.…”

The effect of induced heat waves on Pinus taeda and Quercus rubra seedlings in ambient and elevated CO2 atmospheres

“…This phenomenon has been reported for some conifer and deciduous tree species (Medlyn et al ., ; Hikosaka et al ., ; Ghannoum et al ., ; Gunderson et al ., ), but most studies have shown no acclimatization of photosynthesis to temperature (e.g. Ow et al ., ,b). Our observations indicated that a constant temperature increase of 3°C did not have a significant effect on A net in P. taeda or Q. rubra , compared with A net at ambient temperature.…”

Consequences of complex environments: Temperature and energy intake interact to influence growth and metabolic rate

“…Hypometabolism as an acclimating effect may be a fundamental aspect of thermal plasticity, and it should be considered when constructing animal energy budgets in the context of GCC. It may also be a universal response by organisms to prolonged shifts in temperature as it has been documented in a broad range of taxa (plants: Ow et al, 2008a;Ow et al, 2008b;fungi: Malcolm et al 2008;crustaceans: Powell and Watts, 2006;insects: Lachenicht et al 2010;fishes: Donelson et al 2011, Strobel et al 2012amphibians: Seebacher and Grigaltchik, 2014;reptiles: this study;birds: Abdelqader and Al-Fataftah, 2014;mammals: Geiser et al 2003). However, these studies did not control for variation in energy intake or food availability, which can covary with climatic temperature shifts (Both and Visser, 2005;Altermatt, 2010;Pearce-Higgins et al, 2010;Allan et al, 2013;Cahill et al, 2013).…”