Metabolic responses to waterlogging differ between roots and shoots and reflect phloem transport alteration in medicago truncatula
Root oxygen deficiency that is induced by flooding (waterlogging) is a common situation in many agricultural areas, causing considerable loss in yield and productivity. Physiological and metabolic acclimation to hypoxia has mostly been studied on roots or whole seedlings under full submergence. The metabolic difference between shoots and roots during waterlogging, and how roots and shoots communicate in such a situation is much less known. In particular, the metabolic acclimation in shoots and...[Show more]
|Limami, Anis M.
|Root oxygen deficiency that is induced by flooding (waterlogging) is a common situation in many agricultural areas, causing considerable loss in yield and productivity. Physiological and metabolic acclimation to hypoxia has mostly been studied on roots or whole seedlings under full submergence. The metabolic difference between shoots and roots during waterlogging, and how roots and shoots communicate in such a situation is much less known. In particular, the metabolic acclimation in shoots and how this, in turn, impacts on roots metabolism is not well documented. Here, we monitored changes in the metabolome of roots and shoots of barrel clover (Medicago truncatula), growth, and gas-exchange, and analyzed phloem sap exudate composition. Roots exhibited a typical response to hypoxia, such as γ-aminobutyrate and alanine accumulation, as well as a strong decline in raffinose, sucrose, hexoses, and pentoses. Leaves exhibited a strong increase in starch, sugars, sugar derivatives, and phenolics (tyrosine, tryptophan, phenylalanine, benzoate, ferulate), suggesting an inhibition of sugar export and their alternative utilization by aromatic compounds production via pentose phosphates and phosphoenolpyruvate. Accordingly, there was an enrichment in sugars and a decline in organic acids in phloem sap exudates under waterlogging. Mass-balance calculations further suggest an increased imbalance between loading by shoots and unloading by roots under waterlogging. Taken as a whole, our results are consistent with the inhibition of sugar import by waterlogged roots, leading to an increase in phloem sugar pool, which, in turn, exert negative feedback on sugar metabolism and utilization in shoots.
|This research was funded by the Région Pays de la Loire and Angers Loire Métropole, via the grant Connect Talent Isoseed
|© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
|Metabolic responses to waterlogging differ between roots and shoots and reflect phloem transport alteration in medicago truncatula
|Imported from ARIES
|310806 - Plant physiology
|Lothier, Jeremy, Université d’Angers
|Diab, Houssein, Université d’Angers
|Cukier, Caroline, Université d’Angers
|Limami, Anis M., University of Angers
|Tcherkez, Guillaume, College of Science, ANU
|280102 - Expanding knowledge in the biological sciences
|This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
|Creative Commons Attribution (CC BY) license
|ANU Research Publications
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