skip to main content


Title: First‐year Acacia seedlings are anisohydric “water‐spenders” but differ in their rates of water use
Award ID(s):
2105917
NSF-PAR ID:
10353461
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
American Journal of Botany
Volume:
109
Issue:
8
ISSN:
0002-9122
Page Range / eLocation ID:
1251 to 1261
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. null (Ed.)
    Recently, Gallo et al. ( Chem. Sci., 2019, 10, 2566) investigated whether the previously reported oligomerization of isoprene vapor on the surface of pH < 4 water in an electrospray ionization (ESI) mass spectrometer ( J. Phys. Chem. A, 2012, 116, 6027 and Phys. Chem. Chem. Phys., 2018, 20, 15400) would also proceed in liquid isoprene–acidic water emulsions. Gallo et al. hypothesized that emulsified liquid isoprene would oligomerize on the surface of acidic water because, after all, isoprene, liquid or vapor, is always a hydrophobe. In their emulsion experiments, isoprene oligomers were to be detected by ex situ proton magnetic resonance ( 1 H-NMR) spectrometry. 
    more » « less
  2. Abstract

    Stomatal regulation is crucial for forest species performance and survival on drought‐prone sites. We investigated the regulation of root and shoot hydraulics in threePinus radiataclones exposed to drought stress and its coordination with stomatal conductance (gs) and leaf water potential (Ψleaf). All clones experienced a substantial decrease in root‐specific root hydraulic conductance (Kroot‐r) in response to the water stress, but leaf‐specific shoot hydraulic conductance (Kshoot‐l) did not change in any of the clones. The reduction inKroot‐rcaused a decrease in leaf‐specific whole‐plant hydraulic conductance (Kplant‐l). Among clones, the larger the decrease inKplant‐l, the more stomata closed in response to drought. Rewatering resulted in a quick recovery ofKroot‐randgs. Our results demonstrated that the reduction inKplant‐l, attributed to a down regulation of aquaporin activity in roots, was linked to the isohydric stomatal behaviour, resulting in a nearly constant Ψleafas water stress started. We concluded that higherKplant‐lis associated with water stress resistance by sustaining a less negative Ψleafand delaying stomatal closure.

     
    more » « less
  3. Abstract

    Water supply limitations will likely impose increasing restrictions on future crop production, underlining a need for crops that use less water per mass of yield. Water use efficiency (WUE) therefore becomes a key consideration in developing resilient and productive crops. In this study, we hypothesized that it is possible to improve WUE under drought conditions via modulation of chloroplast signals for stomatal opening by up-regulation of non-photochemical quenching (NPQ). Nicotiana tabacum plants with strong overexpression of the PsbS gene encoding PHOTOSYSTEM II SUBUNIT S, a key protein in NPQ, were grown under differing levels of drought. The PsbS-overexpressing lines lost 11% less water per unit CO2 fixed under drought and this did not have a significant effect on plant size. Depending on growth conditions, the PsbS-overexpressing lines consumed from 4–30% less water at the whole-plant level than the corresponding wild type. Leaf water and chlorophyll contents showed a positive relation with the level of NPQ. This study therefore provides proof of concept that up-regulation of NPQ can increase WUE, and as such is an important step towards future engineering of crops with improved performance under drought.

     
    more » « less