Journal
FIELD CROPS RESEARCH
Volume 162, Issue -, Pages 77-86Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.fcr.2014.02.004
Keywords
Abscisic acid; Leaf water potential; Specific root length; Isohydric; Anisohydric
Categories
Funding
- Endeavour Scholarships
- University of Western Australia's Institute of Agriculture
- Endeavour Fellowships
- School of Plant Biology
Ask authors/readers for more resources
Wheat grown in the Mediterranean-type environments of southern Australia is often exposed to end-of-season drought (terminal drought). During the development of terminal drought, soil dries from the top of the profile exposing the upper part of the root system to water stress while deeper roots may still be able to access deeper soil water for grain filling. It is hypothesised that the part of the root system exposed to drying soil signals abscisic acid (ABA) production and the corresponding rise in ABA concentration in leaves causes partial stomatal closure, regulating the extraction of available water at depth. In the first step to test this hypothesis, a glasshouse experiment was conducted to identify contrasting stomatal response to terminal drought and production of ABA using four wheat genotypes adapted to different soil moisture environments. Terminal drought was induced by withholding water from anthesis in one half (WD) or both halves (DD) of the root system using split pots. Stomatal conductance decreased in all four genotypes in WD plants, but leaf ABA concentration and leaf water status differed. The cultivar Drysdale had higher leaf ABA concentrations and lower stomatal conductance, but leaf water status decreased. Leaf ABA concentration did not increase in WD plants of the breeding line IGW-3262, but stomatal conductance decreased and leaf water status was unchanged. All the genotypes behaved similarly under DD conditions, with increased leaf ABA concentration, lower stomatal conductance and severely dehydrated leaves. The possible causes of the above differences in leaf ABA concentration despite similar stomatal behaviour in wheat genotypes are discussed. (C) 2014 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available