Rights statement: This is the author’s version of a work that was accepted for publication in Environmental and Experimental Botany. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Environmental and Experimental Botany, 179, 2020 DOI: 10.1016/j.envexpbot.2020.104233
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Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Aluminum-induced stomatal closure is related to low root hydraulic conductance and high ABA accumulation
AU - Gavassi, M.A.
AU - Dodd, I.C.
AU - Puértolas, J.
AU - Silva, G.S.
AU - Carvalho, R.F.
AU - Habermann, G.
N1 - This is the author’s version of a work that was accepted for publication in Environmental and Experimental Botany. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Environmental and Experimental Botany, 179, 2020 DOI: 10.1016/j.envexpbot.2020.104233
PY - 2020/11/1
Y1 - 2020/11/1
N2 - Many studies ask how aluminum (Al) reduces the root growth, but as Al is mostly retained in the root system, physiological explanations for the also expected Al-induced decrease in stomatal conductance (gs) are unclear, mainly in well-watered conditions. We exposed tomato plants (Solanum lycopersicum) to 0, 25, 50 and 100 μM Al in nutrient solution to investigate whether Al impairs root hydraulic conductance (Lpr), affecting leaf water potential (Ψleaf) and possibly inducing abscisic acid (ABA) accumulation in roots and/or leaves. We also measured ABA delivery rate, xylem sap pH and the root/leaf area ratio in order to explain the low gs in plants exposed to Al. Declines in Lpr and gs were proportional to the increase in Al concentration, and all Al treatments similarly decreased Ψleaf, indicating the plant's attempt to reduce water loss through transpiration while accumulating more ABA. Despite Al-induced increases in root ABA, the root-to-shoot delivery of ABA did not enhance, but Al caused root xylem sap alkalization. Despite the stability of root/leaf area ratio across a range of Al concentrations (0, 25 and 50 μM Al), the leaf hydration and stomatal opening was not conserved. Here we provide the first evidence that decreases in Lpr and increases in ABA might explain Al-induced stomatal closure. © 2020 Elsevier B.V.
AB - Many studies ask how aluminum (Al) reduces the root growth, but as Al is mostly retained in the root system, physiological explanations for the also expected Al-induced decrease in stomatal conductance (gs) are unclear, mainly in well-watered conditions. We exposed tomato plants (Solanum lycopersicum) to 0, 25, 50 and 100 μM Al in nutrient solution to investigate whether Al impairs root hydraulic conductance (Lpr), affecting leaf water potential (Ψleaf) and possibly inducing abscisic acid (ABA) accumulation in roots and/or leaves. We also measured ABA delivery rate, xylem sap pH and the root/leaf area ratio in order to explain the low gs in plants exposed to Al. Declines in Lpr and gs were proportional to the increase in Al concentration, and all Al treatments similarly decreased Ψleaf, indicating the plant's attempt to reduce water loss through transpiration while accumulating more ABA. Despite Al-induced increases in root ABA, the root-to-shoot delivery of ABA did not enhance, but Al caused root xylem sap alkalization. Despite the stability of root/leaf area ratio across a range of Al concentrations (0, 25 and 50 μM Al), the leaf hydration and stomatal opening was not conserved. Here we provide the first evidence that decreases in Lpr and increases in ABA might explain Al-induced stomatal closure. © 2020 Elsevier B.V.
KW - Abscisic acid
KW - Aluminum
KW - Stomatal conductance
KW - Water transport
KW - Xylem sap pH
KW - abscisic acid
KW - aluminum
KW - concentration (composition)
KW - hydration
KW - hydraulic conductivity
KW - hydraulic property
KW - phytohormone
KW - root system
KW - sap flow
KW - stomatal conductance
KW - transpiration
KW - vegetable
KW - xylem
KW - Lycopersicon esculentum
U2 - 10.1016/j.envexpbot.2020.104233
DO - 10.1016/j.envexpbot.2020.104233
M3 - Journal article
VL - 179
JO - Environmental and Experimental Botany
JF - Environmental and Experimental Botany
SN - 0098-8472
M1 - 104233
ER -