TY  - JOUR
AU  - Müllers, Yannik
AU  - Postma, Johannes A.
AU  - Poorter, Hendrik
AU  - van Dusschoten, Dagmar
TI  - Deep‐water uptake under drought improved due to locally increased root conductivity in maize, but not in faba bean
JO  - Plant, cell & environment
VL  - 46
IS  - 7
SN  - 0140-7791
CY  - Oxford [u.a.]
PB  - Wiley-Blackwell
M1  - FZJ-2023-01665
SP  - 2046-2060
PY  - 2023
AB  - Moderate soil drying can cause a strong decrease in the soil-root system conductance. The resulting impact on root water uptake depends on the spatial distribution of the altered conductance relatively to remaining soil water resources, which is largely unknown. Here, we analyzed the vertical distribution of conductance across root systems using a novel, noninvasive sensor technology on pot-grown faba bean and maize plants. Withholding water for 4 days strongly enhanced the vertical gradient in soil water potential. Therefore, roots in upper and deeper soil layers were affected differently: In drier, upper layers, root conductance decreased by 66%–72%, causing an amplification of the drop in leaf water potential. In wetter, deeper layers, root conductance increased in maize but not in faba bean. The consequently facilitated deep-water uptake in maize contributed up to 21% of total water uptake at the end of the measurement. Analysis of root length distributions with MRI indicated that the locally increased conductance was mainly caused by an increased intrinsic conductivity and not by additional root growth. Our findings show that plants can partly compensate for a reduced root conductance in upper, drier soil layers by locally increasing root conductivity in wetter layers, thereby improving deep-water uptake.
LB  - PUB:(DE-HGF)16
C6  - 36942406
UR  - <Go to ISI:>//WOS:000960343500001
DO  - DOI:10.1111/pce.14587
UR  - https://juser.fz-juelich.de/record/1006430
ER  -