Supplementary calcium overcomes nocturnal chilling‐induced carbon source‐sink limitations of cyclic electron transport in peanuts

Abstract

‘Calcium (Ca²⁺) priming’ is an effective strategy to restore efficient carbon assimilation with undergoing unfavourable cold stress (day/night: 25°C/8°C). However, it is unclear how exogenous calcium strengthens the cyclic electron transfer (CET) to attain optimal carbon flux. To assess the nutrient fortification role of Ca²⁺ (15 mM) in facilitating this process for peanuts, we added antimycin (AA, 100 μM) and rotenone (R, 100 μM) as specific inhibitors. Our results revealed that inhibiting CET caused a negative effect on photosynthesis. The Ca²⁺ treatment accelerated the turnover of non-structural carbohydrates, and linear electron carriers while balancing the photosystem I (PSI) bilateral redox potential. The treatment also strengthened the PROTON GRADIENT REGULATION5 (PGR5)/PGR5-LIKE PHOTOSYNTHETIC PHENOTYPE1 (PGRL1) and the NADH dehydrogenase-like (NDH)-mediated CET, with plausible crosstalk between thioredoxin (Trx) system and Ca²⁺ signalling, to regulate chloroplast redox homoeostasis. Specifically, exogenous Ca²⁺ strengthened the PGR5/PGRL1-mediated CET by providing sufficient ATP and adequate photoprotection during the long-term exposure; the NDH-mediated CET served to alleviate limitations on the PSI acceptor side by translocating protons. This study demonstrated the effectiveness of harnessing optimal nutrient supply, in the form of foliar Ca²⁺-based sprays to strengthen the eco-physiological resilience of peanuts against cold stress.

Published in

Plant, Cell and Environment
2025

SLU Authors

• Yong, Jean W.H

  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Biochemistry
Botany
Horticulture

Publication identifier

• DOI: https://doi.org/10.1111/pce.15467

Permanent link to this page (URI)

https://res.slu.se/id/publ/141383