TY - JOUR

T1 - Crosstalk between ABA and Ethylene in Regulating Stomatal Behavior under High CO2 and Progressive Soil Drying

AU - Liang, Kehao

AU - Chen, Xuefei

AU - Liu, Fulai

N1 - © The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

PY - 2023

Y1 - 2023

N2 - Increasing atmospheric CO2 concentrations accompanied by intensified drought stress have a significant impact on plant growth and physiology. The aim of this study was to explore the role of abscisic acid (ABA) in mediating the response of stomata to elevated CO2 (e[CO2]) and soil water deficits. Tomato plants with different endogenous ABA concentrations (Ailsa Craig (AC), its ABA-deficient mutant (flacca) and ABA-overproduction transgenic tomato (SP5)) were grown in ambient (a[CO2], 400 μmol mol -1) and elevated (800 μmol mol -1) CO2 environments and were subjected to progressive soil drying at six-leaf stage. Results showed that, compared to plants grown under a[CO2], e[CO2]-plants had significantly lower stomatal conductance in AC and SP5 but not in flacca. Under drought, e[CO2]-plants had better water status and higher water use efficiency at both leaf and whole plant levels. e[CO2] had no effects on the ABA concentration of plants under well-watered conditions but promoted the accumulation of ABA in leaves of plants subjected to drought stress, which coincided with the upregulated expression of ABA biosynthetic genes and downregulated expression of ABA metabolic genes. Although in flacca, the increase of ABA induced by drought was much less than in AC and SP5, it accumulated large amounts of ethylene, suggesting that in plants with ABA deficiency, ethylene may play a compensatory role in inducing stomatal closure during soil drying. Collectively, these findings improve our understanding of plant performances to a future drier and CO2-enriched environment.

AB - Increasing atmospheric CO2 concentrations accompanied by intensified drought stress have a significant impact on plant growth and physiology. The aim of this study was to explore the role of abscisic acid (ABA) in mediating the response of stomata to elevated CO2 (e[CO2]) and soil water deficits. Tomato plants with different endogenous ABA concentrations (Ailsa Craig (AC), its ABA-deficient mutant (flacca) and ABA-overproduction transgenic tomato (SP5)) were grown in ambient (a[CO2], 400 μmol mol -1) and elevated (800 μmol mol -1) CO2 environments and were subjected to progressive soil drying at six-leaf stage. Results showed that, compared to plants grown under a[CO2], e[CO2]-plants had significantly lower stomatal conductance in AC and SP5 but not in flacca. Under drought, e[CO2]-plants had better water status and higher water use efficiency at both leaf and whole plant levels. e[CO2] had no effects on the ABA concentration of plants under well-watered conditions but promoted the accumulation of ABA in leaves of plants subjected to drought stress, which coincided with the upregulated expression of ABA biosynthetic genes and downregulated expression of ABA metabolic genes. Although in flacca, the increase of ABA induced by drought was much less than in AC and SP5, it accumulated large amounts of ethylene, suggesting that in plants with ABA deficiency, ethylene may play a compensatory role in inducing stomatal closure during soil drying. Collectively, these findings improve our understanding of plant performances to a future drier and CO2-enriched environment.

U2 - 10.1093/jxb/erad309

DO - 10.1093/jxb/erad309

M3 - Journal article

C2 - 37540146

VL - 74

SP - 5931

EP - 5946

JO - Journal of Experimental Botany

JF - Journal of Experimental Botany

SN - 0022-0957

IS - 18

ER -