Ecophysiological processes underlying soybean mineral nutrition under individual or combined heat and water stresses
Résumé
In a context of climate change, with more frequent drought events and heatwaves, it is
predicted that soybean yields will drastically decrease in the near future. Soybean being the
most widely grown legume crop in the world, there is an urgent need to improve its ability to
sustain its growth under such conditions in order to guarantee high levels of productivity. The
aim of this study was to explore the influence of heat and/or water stress on soybean growth
and its water and mineral nutritions. Two soybean genotypes, displaying contrasted root
architectures during their vegetative stage were grown under controlled conditions in the
4PMI high-throughput phenotyping platform where either optimal conditions, or heatwaves,
or water stress, or both heatwaves and water stress were applied. Plants were characterized for
their morphology, their water uptake, the mineral composition of their tissues and the root
transcriptome. An ecophysiological structure-function framework, enabled us to link
structural variables (leaf area, root architecture, biomass, etc.) to functional variables (water
use efficiency, element uptake efficiencies…) in order to understand the interactions between
water and element fluxes, and to quantify the overall tolerance of plants to each stress. Under
combined stress conditions, one genotype appeared more sensitive than the other. No
significant changes in structural variables were observed in response to the dual stress
between the two genotypes. However, the genotypic difference was found to be more related
to functional changes, particularly for water uptake. A complementary analysis of the plant
ionome and transcriptome under different stresses revealed plant strategies favoring soybean
growth under these two stresses, and offered new perspectives for crop adaptation to climate
change.
Domaines
Sciences du Vivant [q-bio]Origine | Fichiers produits par l'(les) auteur(s) |
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