@article{Zhou:2015:aob/mcv161,
author = {Zhou, S-X and Medlyn, BE and Prentice, IC},
doi = {aob/mcv161},
journal = {Annals of Botany},
pages = {133--144},
title = {Long-term water stress leads to acclimation of drought sensitivity of photosynthetic capacity in xeric but not riparian Eucalyptus species},
url = {http://dx.doi.org/10.1093/aob/mcv161},
volume = {117},
year = {2015}
}

Download

TY  - JOUR
AB  - Background and Aims Experimental drought is well documented to induce a decline in photosynthetic capacity. However, if given time to acclimate to low water availability, the photosynthetic responses of plants to low soil moisture content may differ from those found in short-term experiments. This study aims to test whether plants acclimate to long-term water stress by modifying the functional relationships between photosynthetic traits and water stress, and whether species of contrasting habitat differ in their degree of acclimation.Methods Three Eucalyptus taxa from xeric and riparian habitats were compared with regard to their gas exchange responses under short- and long-term drought. Photosynthetic parameters were measured after 2 and 4 months of watering treatments, namely field capacity or partial drought. At 4 months, all plants were watered to field capacity, then watering was stopped. Further measurements were made during the subsequent ‘drying-down’, continuing until stomata were closed.Key Results Two months of partial drought consistently reduced assimilation rate, stomatal sensitivity parameters (g1), apparent maximum Rubisco activity (V′cmaxVcmax′) and maximum electron transport rate (J′maxJmax′). Eucalyptus occidentalis from the xeric habitat showed the smallest decline in V′cmaxVcmax′ and J′maxJmax′; however, after 4 months, V′cmaxVcmax′ and J′maxJmax′ had recovered. Species differed in their degree of V′cmaxVcmax′ acclimation. Eucalyptus occidentalis showed significant acclimation of the pre-dawn leaf water potential at which the V′cmaxVcmax′ and ‘true’ Vcmax (accounting for mesophyll conductance) declined most steeply during drying-down.Conclusions The findings indicate carbon loss under prolonged drought could be over-estimated without accounting for acclimation. In particular, (1) species from contrasting habitats differed in th
AU  - Zhou,S-X
AU  - Medlyn,BE
AU  - Prentice,IC
DO  - aob/mcv161
EP  - 144
PY  - 2015///
SN  - 1095-8290
SP  - 133
TI  - Long-term water stress leads to acclimation of drought sensitivity of photosynthetic capacity in xeric but not riparian Eucalyptus species
T2  - Annals of Botany
UR  - http://dx.doi.org/10.1093/aob/mcv161
UR  - http://hdl.handle.net/10044/1/56802
VL  - 117
ER  - 

Download