Abstract
Key Message
Short-term exposure to high temperatures modulates the aromatic cytokinin profile of radiata pine embryonal masses when measured 8 weeks after initiation.
Abstract Recent research has demonstrated that cytokinins could be involved in abiotic stress responses. However, little research has been published about the role of endogenous aromatic cytokinins during these processes. Therefore, in this study, different temperature and incubation periods (23 ºC, 8 weeks; 40 ºC, 4 h; 50 ºC, 30 min; 60 ºC, 5 min) were applied during induction of radiata pine somatic embryogenesis and the aromatic cytokinin content of the resulting embryonal masses was measured. Results indicated that temperature during induction had a significant effect on the profile of most of the aromatic cytokinins detected. All tested higher temperatures than control provoked a decline in some free bases, including N6-benzyladenine, ortho-Topolin and para-Topolin. On the other hand, the values of N6-benzyladenine nucleotides, ribosides and irreversible metabolites (9G), as well as para-Topolin ribosides, increased in embryonal masses originating from 40 ºC treatment. These results suggest that despite not being traditionally considered part of the stress response machinery, aromatic cytokinins might be involved in heat-stress responses during early stages of somatic embryogenesis in radiata pine.
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Abbreviations
- CK:
-
Cytokinins
- SE:
-
Somatic embryogenesis
- EM:
-
Embryonal mass
- ECL:
-
Established cell line
- BA:
-
N6-Benzyladenine
- BAR:
-
N6-Benzyladenosine
- BARMP:
-
N6-Benzyladenosine-5′monophosphate
- BA7G:
-
N6-Benzyladenine-7-glucoside
- BA9G:
-
N6-Benzyladenine-9-glucoside
- oT:
-
ortho-Topolin
- oTR:
-
ortho-Topolin riboside
- oT7G:
-
ortho-Topolin-7-glucoside
- oT9G:
-
ortho-Topolin-9-glucoside
- mT:
-
meta-Topolin
- mTR:
-
meta-Topolin riboside
- mT7G:
-
meta-Topolin-7-glucoside
- mT9G:
-
meta-Topolin-9-glucoside
- pT:
-
para-Topolin
- pTR:
-
para-Topolin riboside
- pT7G:
-
para-Topolin-7-glucoside
- pT9G:
-
para-Topolin-9-glucoside
- K:
-
Kinetin
- KR:
-
Kinetin riboside
- K9G:
-
Kinetin-9-glucoside
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Funding
This research was funded by MINECO project (AGL2016-76143-C4-3R), CYTED (P117RT0522), DECO (Basque government) and MULTIFOREVER project, supported under the umbrella of ERA-NET Cofund ForestValue by ANR (FR), FNR (DE), MINCyT (AR), MINECO-AEI (ES), MMM (FI) and VINNOVA (SE). ForestValue has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 773324. This work was also supported by the Internal Grant Agency of Palacký University (IGA_PrF_2020_021) and from European Regional Development Fund-Project "Plants as a tool for sustainable global development" (No. CZ.02.1.01/0.0/0.0/16_019/0000827).
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Castander-Olarieta, A., Pereira, C., Montalbán, I.A. et al. Quantification of endogenous aromatic cytokinins in Pinus radiata embryonal masses after application of heat stress during initiation of somatic embryogenesis. Trees 35, 1075–1080 (2021). https://doi.org/10.1007/s00468-020-02047-x
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DOI: https://doi.org/10.1007/s00468-020-02047-x