Heat Waves Change Plant Carbon Allocation Among Primary and Secondary Metabolism Altering CO Assimilation, Respiration, and VOC Emissions
Werner, Christiane (University Freiburg. Institute of Ecosystem Physiology)
Fasbender, Lukas (University Freiburg. Institute of Ecosystem Physiology)
Romek, Katarzyna M. (University of Freiburg. Ecosystem Physiology)
Yáñez Serrano, Ana María (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Kreuzwieser, Jürgen (University Freiburg. Institute of Ecosystem Physiology)

Date:	2020
Abstract:	Processes controlling plant carbon allocation among primary and secondary metabolism, i. e. , carbon assimilation, respiration, and VOC synthesis are still poorly constrained, particularly regarding their response to stress. To investigate these processes, we simulated a 10-day 38°C heat wave, analysing real-time carbon allocation into primary and secondary metabolism in the Mediterranean shrub Halimium halimifolium L. We traced position-specific 13 C-labeled pyruvate into daytime VOC and CO emissions and during light-dark transition. Net CO assimilation strongly declined under heat, due to three-fold higher respiration rates. Interestingly, day respiration also increased two-fold. Decarboxylation of the C1-atom of pyruvate was the main process driving daytime CO release, whereas the C2-moiety was not decarboxylated in the TCA cycle. Heat induced high emissions of methanol, methyl acetate, acetaldehyde as well as mono- and sesquiterpenes, particularly during the first two days. After 10-days of heat a substantial proportion of 13 C-labeled pyruvate was allocated into de novo synthesis of VOCs. Thus, during extreme heat waves high respiratory losses and reduced assimilation can shift plants into a negative carbon balance. Still, plants enhanced their investment into de novo VOC synthesis despite associated metabolic CO losses. We conclude that heat stress re-directed the proportional flux of key metabolites into pathways of VOC biosynthesis most likely at the expense of reactions of plant primary metabolism, which might highlight their importance for stress protection.
Grants:	European Commission 647008
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Carbon allocation ; Day respiration ; Temperature stress ; 13 C position-specific labeling ; Photosynthesis ; Pyruvate ; Dark ; Volatile organic compounds (VOC)
Published in:	Frontiers in plant science, Vol. 11 (August 2020) , art. 1242, ISSN 1664-462X

DOI: 10.3389/fpls.2020.01242
PMID: 32922421

17 p, 2.9 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > CREAF (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Articles > Research articles
Articles > Published articles