Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.
Identifieur interne : 001673 ( Main/Exploration ); précédent : 001672; suivant : 001674Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.
Auteurs : Sergio G. Nebauer [Espagne] ; Bego A Renau-Morata ; José Luis Guardiola ; Rosa-Victoria MolinaSource :
- Tree physiology [ 1758-4469 ] ; 2011.
English descriptors
- KwdEn :
- MESH :
- chemical , metabolism : Starch.
- genetics : Carbohydrate Metabolism, Citrus sinensis.
- metabolism : Citrus sinensis, Fruit, Plant Leaves.
- physiology : Carbohydrate Metabolism.
- Biological Transport, Down-Regulation, Photosynthesis.
Abstract
Photosynthesis down-regulation due to an imbalance between sources and sinks in Citrus leaves could be mediated by excessive accumulation of carbohydrates. However, there is limited understanding of the physiological role of soluble and insoluble carbohydrates in photosynthesis regulation and the elements triggering the down-regulation process. In this work, the role of non-structural carbohydrates in the regulation of photosynthesis under a broad spectrum of source-sink relationships has been investigated in the Salustiana sweet orange. Soluble sugar and starch accumulation in leaves, induced by girdling experiments, did not induce down-regulation of the photosynthetic rate in the presence of sinks (fruits). The leaf-to-fruit ratio did not modulate photosynthesis but allocation of photoassimilates to the fruits. The lack of strong sink activity led to a decrease in the photosynthetic rate and starch accumulation in leaves. However, photosynthesis down-regulation due to an excess of total soluble sugars or starch was discarded because photosynthesis and stomatal conductance reduction occurred prior to any significant accumulation of these carbohydrates. Gas exchange and fluorescence parameters suggested biochemical limitations to photosynthesis. In addition, the expression of carbon metabolism-related genes was altered within 24 h when strong sinks were removed. Sucrose synthesis and export genes were inhibited, whereas the expression of ADP-glucose pyrophosphorylase was increased to cope with the excess of assimilates. In conclusion, changes in starch and soluble sugar turnover, but not sugar content per se, could provide the signal for photosynthesis regulation. In these conditions, non-stomatal limitations strongly inhibited the photosynthetic rate prior to any significant increase in carbohydrate levels.
DOI: 10.1093/treephys/tpq103
PubMed: 21367744
Affiliations:
Links toward previous steps (curation, corpus...)
- to stream PubMed, to step Corpus: 000763
- to stream PubMed, to step Curation: 000763
- to stream PubMed, to step Checkpoint: 000763
- to stream Ncbi, to step Merge: 000D05
- to stream Ncbi, to step Curation: 000D05
- to stream Ncbi, to step Checkpoint: 000D05
- to stream Main, to step Merge: 001695
- to stream Main, to step Curation: 001673
Le document en format XML
<record><TEI><teiHeader><fileDesc><titleStmt><title xml:lang="en">Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.</title><author><name sortKey="Nebauer, Sergio G" sort="Nebauer, Sergio G" uniqKey="Nebauer S" first="Sergio G" last="Nebauer">Sergio G. Nebauer</name><affiliation wicri:level="1"><nlm:affiliation>Departamento de Producción Vegetal, Universitat Politècnica de València, Camino de Vera s/n, Valencia, Spain. sergonne@bvg.upv.es</nlm:affiliation><country xml:lang="fr">Espagne</country><wicri:regionArea>Departamento de Producción Vegetal, Universitat Politècnica de València, Camino de Vera s/n, Valencia</wicri:regionArea><wicri:noRegion>Valencia</wicri:noRegion></affiliation></author><author><name sortKey="Renau Morata, Bego A" sort="Renau Morata, Bego A" uniqKey="Renau Morata B" first="Bego A" last="Renau-Morata">Bego A Renau-Morata</name></author><author><name sortKey="Guardiola, Jose Luis" sort="Guardiola, Jose Luis" uniqKey="Guardiola J" first="José Luis" last="Guardiola">José Luis Guardiola</name></author><author><name sortKey="Molina, Rosa Victoria" sort="Molina, Rosa Victoria" uniqKey="Molina R" first="Rosa-Victoria" last="Molina">Rosa-Victoria Molina</name></author></titleStmt><publicationStmt><idno type="wicri:source">PubMed</idno><date when="2011">2011</date><idno type="RBID">pubmed:21367744</idno><idno type="pmid">21367744</idno><idno type="doi">10.1093/treephys/tpq103</idno><idno type="wicri:Area/PubMed/Corpus">000763</idno><idno type="wicri:Area/PubMed/Curation">000763</idno><idno type="wicri:Area/PubMed/Checkpoint">000763</idno><idno type="wicri:Area/Ncbi/Merge">000D05</idno><idno type="wicri:Area/Ncbi/Curation">000D05</idno><idno type="wicri:Area/Ncbi/Checkpoint">000D05</idno><idno type="wicri:Area/Main/Merge">001695</idno><idno type="wicri:Area/Main/Curation">001673</idno><idno type="wicri:Area/Main/Exploration">001673</idno></publicationStmt><sourceDesc><biblStruct><analytic><title xml:lang="en">Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.</title><author><name sortKey="Nebauer, Sergio G" sort="Nebauer, Sergio G" uniqKey="Nebauer S" first="Sergio G" last="Nebauer">Sergio G. Nebauer</name><affiliation wicri:level="1"><nlm:affiliation>Departamento de Producción Vegetal, Universitat Politècnica de València, Camino de Vera s/n, Valencia, Spain. sergonne@bvg.upv.es</nlm:affiliation><country xml:lang="fr">Espagne</country><wicri:regionArea>Departamento de Producción Vegetal, Universitat Politècnica de València, Camino de Vera s/n, Valencia</wicri:regionArea><wicri:noRegion>Valencia</wicri:noRegion></affiliation></author><author><name sortKey="Renau Morata, Bego A" sort="Renau Morata, Bego A" uniqKey="Renau Morata B" first="Bego A" last="Renau-Morata">Bego A Renau-Morata</name></author><author><name sortKey="Guardiola, Jose Luis" sort="Guardiola, Jose Luis" uniqKey="Guardiola J" first="José Luis" last="Guardiola">José Luis Guardiola</name></author><author><name sortKey="Molina, Rosa Victoria" sort="Molina, Rosa Victoria" uniqKey="Molina R" first="Rosa-Victoria" last="Molina">Rosa-Victoria Molina</name></author></analytic><series><title level="j">Tree physiology</title><idno type="eISSN">1758-4469</idno><imprint><date when="2011" type="published">2011</date></imprint></series></biblStruct></sourceDesc></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>Biological Transport</term><term>Carbohydrate Metabolism (genetics)</term><term>Carbohydrate Metabolism (physiology)</term><term>Citrus sinensis (genetics)</term><term>Citrus sinensis (metabolism)</term><term>Down-Regulation</term><term>Fruit (metabolism)</term><term>Photosynthesis</term><term>Plant Leaves (metabolism)</term><term>Starch (metabolism)</term></keywords><keywords scheme="MESH" type="chemical" qualifier="metabolism" xml:lang="en"><term>Starch</term></keywords><keywords scheme="MESH" qualifier="genetics" xml:lang="en"><term>Carbohydrate Metabolism</term><term>Citrus sinensis</term></keywords><keywords scheme="MESH" qualifier="metabolism" xml:lang="en"><term>Citrus sinensis</term><term>Fruit</term><term>Plant Leaves</term></keywords><keywords scheme="MESH" qualifier="physiology" xml:lang="en"><term>Carbohydrate Metabolism</term></keywords><keywords scheme="MESH" xml:lang="en"><term>Biological Transport</term><term>Down-Regulation</term><term>Photosynthesis</term></keywords></textClass></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">Photosynthesis down-regulation due to an imbalance between sources and sinks in Citrus leaves could be mediated by excessive accumulation of carbohydrates. However, there is limited understanding of the physiological role of soluble and insoluble carbohydrates in photosynthesis regulation and the elements triggering the down-regulation process. In this work, the role of non-structural carbohydrates in the regulation of photosynthesis under a broad spectrum of source-sink relationships has been investigated in the Salustiana sweet orange. Soluble sugar and starch accumulation in leaves, induced by girdling experiments, did not induce down-regulation of the photosynthetic rate in the presence of sinks (fruits). The leaf-to-fruit ratio did not modulate photosynthesis but allocation of photoassimilates to the fruits. The lack of strong sink activity led to a decrease in the photosynthetic rate and starch accumulation in leaves. However, photosynthesis down-regulation due to an excess of total soluble sugars or starch was discarded because photosynthesis and stomatal conductance reduction occurred prior to any significant accumulation of these carbohydrates. Gas exchange and fluorescence parameters suggested biochemical limitations to photosynthesis. In addition, the expression of carbon metabolism-related genes was altered within 24 h when strong sinks were removed. Sucrose synthesis and export genes were inhibited, whereas the expression of ADP-glucose pyrophosphorylase was increased to cope with the excess of assimilates. In conclusion, changes in starch and soluble sugar turnover, but not sugar content per se, could provide the signal for photosynthesis regulation. In these conditions, non-stomatal limitations strongly inhibited the photosynthetic rate prior to any significant increase in carbohydrate levels.</div></front></TEI><affiliations><list><country><li>Espagne</li></country></list><tree><noCountry><name sortKey="Guardiola, Jose Luis" sort="Guardiola, Jose Luis" uniqKey="Guardiola J" first="José Luis" last="Guardiola">José Luis Guardiola</name><name sortKey="Molina, Rosa Victoria" sort="Molina, Rosa Victoria" uniqKey="Molina R" first="Rosa-Victoria" last="Molina">Rosa-Victoria Molina</name><name sortKey="Renau Morata, Bego A" sort="Renau Morata, Bego A" uniqKey="Renau Morata B" first="Bego A" last="Renau-Morata">Bego A Renau-Morata</name></noCountry><country name="Espagne"><noRegion><name sortKey="Nebauer, Sergio G" sort="Nebauer, Sergio G" uniqKey="Nebauer S" first="Sergio G" last="Nebauer">Sergio G. Nebauer</name></noRegion></country></tree></affiliations></record>Pour manipuler ce document sous Unix (Dilib)
EXPLOR_STEP=$WICRI_ROOT/Wicri/Bois/explor/OrangerV1/Data/Main/Exploration
HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 001673 | SxmlIndent | more
Ou
HfdSelect -h $EXPLOR_AREA/Data/Main/Exploration/biblio.hfd -nk 001673 | SxmlIndent | more
Pour mettre un lien sur cette page dans le réseau Wicri
{{Explor lien
|wiki= Wicri/Bois
|area= OrangerV1
|flux= Main
|étape= Exploration
|type= RBID
|clé= pubmed:21367744
|texte= Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.
}}
Pour générer des pages wiki
HfdIndexSelect -h $EXPLOR_AREA/Data/Main/Exploration/RBID.i -Sk "pubmed:21367744" \
| HfdSelect -Kh $EXPLOR_AREA/Data/Main/Exploration/biblio.hfd \
| NlmPubMed2Wicri -a OrangerV1
| This area was generated with Dilib version V0.6.25. |  |