The role of potassium on maize leaf carbon exportation under drought condition

Autor: Jean-Christophe Domec, Masako Dannoura, Alexandre Bosc, Lionel Jordan-Meille, Elsa Martineau, Yves Gibon, Camille Bénard
Přispěvatelé: Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Kyoto University [Kyoto], Biologie du fruit et pathologie (BFP), Université Sciences et Technologies - Bordeaux 1-Université Bordeaux Segalen - Bordeaux 2-Institut National de la Recherche Agronomique (INRA)
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Acta Physiologiae Plantarum
Acta Physiologiae Plantarum, Springer Verlag, 2017, 39 (10), pp.1-13. ⟨10.1007/s11738-017-2515-5⟩
ISSN: 0137-5881
1861-1664
DOI: 10.1007/s11738-017-2515-5⟩
Popis: UMR BFP - Equipe Meta; International audience; Climate changes are mainly characterized by an increase in air temperature and a decrease in rainfalls. Potassium (K) nutrition is generally considered to alleviate plants tolerance to water deficit, especially by improving photosynthesis and phloem transport of carbohydrates from leaves to roots. The main objective of this study was to measure the effect of K on sugar transport and allocation under water-stressed conditions on maize (Zea mays L.). Maize plants were grown in pots under different water and K treatments. We used 13CO2 pulse-labelling to determine carbon exportation from leaves with δ13C analysis, within 1 week. The diurnal sugar content in leaves was measured, and net carbon assimilation accessed. Water deficit strongly reduced plant growth, while K nutrition appeared to be efficient in attenuating these effects. K deficiency significantly decreased starch content in leaves under well-watered but not under water-stressed treatment. A leaf carbon mass balance showed that K increased sugar export on a daily time scale, while instantaneous δ13C measurements did not show any significant effect, partly because of the very rapid δ13C decline after labelling. Our home-made labelling chamber proved to be successful in monitoring diurnal changes in δ13C for a C4 plant with high photosynthetic rates and fast carbon export, and also in determining the effect of a K deficiency on sugar export. Our results highlight a need for research into carbon export on leaves of different ages in fast-growing crops under the combined effect of water and nutrient stress.
Databáze: OpenAIRE
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