TY  - JOUR
AU  - Schneider, Hannah
AU  - Postma, Johannes Auke
AU  - Wojciechowski, Tobias
AU  - Kuppe, Christian
AU  - Lynch, Jonathan
TI  - Root Cortical Senescence Improves Growth under Suboptimal Availability of N, P, and K
JO  - Plant physiology
VL  - 174
IS  - 4
SN  - 1532-2548
CY  - Rockville, Md.
PB  - Soc.
M1  - FZJ-2017-04566
SP  - 2333–2347
PY  - 2017
AB  - Root cortical senescence (RCS) in Triticeae reduces nutrient uptake, nutrient content, respiration, and radial hydraulic conductance of root tissue. We used the functional-structural model SimRoot to evaluate the functional implications of RCS in barley (Hordeum vulgare) under suboptimal nitrate, phosphorus, and potassium availability. The utility of RCS was evaluated using sensitivity analyses in contrasting nutrient regimes. At flowering (80 d), RCS increased simulated plant growth by up to 52%, 73%, and 41% in nitrate-, phosphorus-, and potassium-limiting conditions, respectively. Plants with RCS had reduced nutrient requirement of root tissue for optimal plant growth, reduced total cumulative cortical respiration, and increased total carbon reserves. Nutrient reallocation during RCS had a greater effect on simulated plant growth than reduced respiration or nutrient uptake. Under low nutrient availability, RCS had greater benefit in plants with fewer tillers. RCS had greater benefit in phenotypes with fewer lateral roots at low nitrate availability, but the opposite was true in low phosphorus or potassium availability. Additionally, RCS was quantified in field-grown barley in different nitrogen regimes. Field and virtual soil coring simulation results demonstrated that living cortical volume per root length (an indicator of RCS) decreased with depth in younger plants, while roots of older plants had very little living cortical volume per root length. RCS may be an adaptive trait for nutrient acquisition by reallocating nutrients from senescing tissue and secondarily by reducing root respiration. These simulated results suggest that RCS merits investigation as a breeding target for enhanced soil resource acquisition and edaphic stress tolerance.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000406865900028
C6  - pmid:28667049
DO  - DOI:10.1104/pp.17.00648
UR  - https://juser.fz-juelich.de/record/834662
ER  -