Diurnal variations in abscisic acid content and stomatal response to applied abscisic acid in leaves of irrigated and non-irrigated Arbutus unedo plants under naturally fluctuating environmental conditions

Diurnal variations in abscisic acid content and stomatal response to applied abscisic acid in... Endogenous abscisic acid content (ABA) of Arbutus unedo leaves growing under natural conditions in a macchia near Sobreda, Portugal, was very high (0.25 to 2.3 μg g 1 fresh weight). Highest concentrations were found during the very early morning hours and at midday. During the late morning hours and in the late afternoon ABA concentrations decreased to between one-third and one-fourth of peak values. The samples for ABA content were obtained from both irrigated (Ψ between-10 and-25 bar) and non-irrigated plants experiencing natural water stress during the dry season (Ψ of-50 bar). During the course of the measurement day, stomatal conductance was relatively constant and conductance of watered plants was 50 to 100% greater than that of unwatered plants. No clear correlations between ABA content and stomatal conductance and/or xylem water potential were observed. Despite large differences in water potential and differences in degree of stomatal opening, absolute concentrations of ABA were not found to differ. Small quantities (8–14 pmoles cm 2 leaf area) of ABA were applied to leaves of irrigated and non-irrigated Arbutus unedo plants by injection into the petiole. These extremely small ABA doses resulted in transient reductions in stomatal conductance. The effectiveness with which injected ABA closed stomata was highest during the morning and decreased substantially at midday. Increased sensitivity to injected ABA may again occur in the late afternoon but recent measurements suggest that this may depend on long-term drought experience of the plants. The characteristics of the response to injected ABA were similar in irrigated and non-irrigated plants although irrigated plants responded in general more strongly. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Oecologia Springer Journals

Diurnal variations in abscisic acid content and stomatal response to applied abscisic acid in leaves of irrigated and non-irrigated Arbutus unedo plants under naturally fluctuating environmental conditions

Oecologia, Volume 58 (1) – Apr 1, 1983

Loading next page...
 
/lp/springer-journals/diurnal-variations-in-abscisic-acid-content-and-stomatal-response-to-vLNS0HKs0O
Publisher
Springer Journals
Copyright
Copyright © 1983 by Springer-Verlag GmbH & CO. KG
Subject
Life Sciences; Ecology; Plant Sciences
ISSN
0029-8549
eISSN
1432-1939
DOI
10.1007/BF00384552
Publisher site
See Article on Publisher Site

Abstract

Endogenous abscisic acid content (ABA) of Arbutus unedo leaves growing under natural conditions in a macchia near Sobreda, Portugal, was very high (0.25 to 2.3 μg g 1 fresh weight). Highest concentrations were found during the very early morning hours and at midday. During the late morning hours and in the late afternoon ABA concentrations decreased to between one-third and one-fourth of peak values. The samples for ABA content were obtained from both irrigated (Ψ between-10 and-25 bar) and non-irrigated plants experiencing natural water stress during the dry season (Ψ of-50 bar). During the course of the measurement day, stomatal conductance was relatively constant and conductance of watered plants was 50 to 100% greater than that of unwatered plants. No clear correlations between ABA content and stomatal conductance and/or xylem water potential were observed. Despite large differences in water potential and differences in degree of stomatal opening, absolute concentrations of ABA were not found to differ. Small quantities (8–14 pmoles cm 2 leaf area) of ABA were applied to leaves of irrigated and non-irrigated Arbutus unedo plants by injection into the petiole. These extremely small ABA doses resulted in transient reductions in stomatal conductance. The effectiveness with which injected ABA closed stomata was highest during the morning and decreased substantially at midday. Increased sensitivity to injected ABA may again occur in the late afternoon but recent measurements suggest that this may depend on long-term drought experience of the plants. The characteristics of the response to injected ABA were similar in irrigated and non-irrigated plants although irrigated plants responded in general more strongly.

Journal

OecologiaSpringer Journals

Published: Apr 1, 1983

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off