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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Rapid changes in root HvPIP2; 2 aquaporins abundance and ABA concentration are required to enhance root hydraulic conductivity and maintain leaf water potential in response to increased evaporative demand
AU - Veselov, Dmitry S.
AU - Sharipova, Guzel V.
AU - Veselov, Stanislav Yu.
AU - Dodd, Ian C.
AU - Ivanov, Igor
AU - Kudoyarova, Guzel R.
PY - 2016/11/9
Y1 - 2016/11/9
N2 - To address the involvement of abscisic acid (ABA) in regulating transpiration and root hydraulic conductivity (Lp(Root)) and their relative importance for maintaining leaf hydration, the ABA-deficient barley mutant Az34 and its parental wild-type (WT) genotype (cv. Steptoe) were grown in hydroponics and exposed to changes in atmospheric vapour pressure deficit (VPD) imposed by air warming. WTplants were capable of maintaining leaf water potential (psi(L)) that was likely due to increased Lp(Root) enabling higher water flow from the roots, which increased in response to air warming. The increased Lp(Root) and immunostaining for HvPIP2; 2 aquaporins (AQPs) correlated with increased root ABA content of WT plants when exposed to increased air temperature. The failure of Az34 to maintain psi(L) during air warming may be due to lower Lp(Root) than WT plants, and an inability to respond to changes in air temperature. The correlation between root ABA content and Lp(Root) was further supported by increased root hydraulic conductivity in both genotypes when treated with exogenous ABA (10(-5) M). Thus the ability of the root system to rapidly regulate ABA levels (and thence aquaporin abundance and hydraulic conductivity) seems important to maintain leaf hydration.
AB - To address the involvement of abscisic acid (ABA) in regulating transpiration and root hydraulic conductivity (Lp(Root)) and their relative importance for maintaining leaf hydration, the ABA-deficient barley mutant Az34 and its parental wild-type (WT) genotype (cv. Steptoe) were grown in hydroponics and exposed to changes in atmospheric vapour pressure deficit (VPD) imposed by air warming. WTplants were capable of maintaining leaf water potential (psi(L)) that was likely due to increased Lp(Root) enabling higher water flow from the roots, which increased in response to air warming. The increased Lp(Root) and immunostaining for HvPIP2; 2 aquaporins (AQPs) correlated with increased root ABA content of WT plants when exposed to increased air temperature. The failure of Az34 to maintain psi(L) during air warming may be due to lower Lp(Root) than WT plants, and an inability to respond to changes in air temperature. The correlation between root ABA content and Lp(Root) was further supported by increased root hydraulic conductivity in both genotypes when treated with exogenous ABA (10(-5) M). Thus the ability of the root system to rapidly regulate ABA levels (and thence aquaporin abundance and hydraulic conductivity) seems important to maintain leaf hydration.
KW - absicisic acid
KW - Hordeum vulgare
KW - tissue hydration
KW - water relations
KW - ABSCISIC-ACID
KW - BARLEY ROOTS
KW - XYLEM SAP
KW - GROWTH
KW - CONDUCTANCE
KW - WHEAT
KW - CHANNELS
KW - TOMATO
KW - TRANSPIRATION
KW - EXPANSION
U2 - 10.1071/FP16242
DO - 10.1071/FP16242
M3 - Journal article
VL - 45
SP - 143
EP - 149
JO - Functional Plant Biology
JF - Functional Plant Biology
SN - 1445-4408
IS - 2
ER -