USP Electronic Research Repository

Delivery rates of abscisic acid in xylem sap of Ricinus communis L. plants subjected to part - drying of the soil

Jokhan, Anjeela D. and Else, Mark A. and Jackson, Michael B. (1996) Delivery rates of abscisic acid in xylem sap of Ricinus communis L. plants subjected to part - drying of the soil. Journal of Experimental Botany, 47 (10). pp. 1595-1599. ISSN 0022-0957

Full text not available from this repository.

Abstract

Abscisic acid (ABA) moving from roots to shoots in the transpiration stream is a potential hormonal message integrating perception of a root stress with adaptive changes in the shoot. A twin root system was used to study ways of estimating effects of droughting the upper roots of Ricinus communis L. on abscisic acid (ABA) transport to the shoot in the transpiration stream. Droughted plants transpired more slowly than controls. Droughting also increased concentrations of ABA up to I I-fold in sap induced to flow from the roots of freshly decapitated plants at rates of whole plant transpiration. However, because of dilution effects arising from the different sap flows in control and droughted plants, these changes in ABA concentration in the xylem sap did not accurately reflect amounts of ABA transported. To overcome this problem, delivery rates were calculated by multiplying concentration with sap flow rate to generate ABA delivery in terms of μmol s−1 per plant. Droughting for 24 h or more increased ABA delivery from roots to shoots by 5-fold. Since droughting can alter the relative sizes of the roots and shoots and also the root:shoot ratio these delivery rates were refined in several ways to reflect both the amount of root generating the ABA message and the size of the recipient shoot system.

Item Type: Journal Article
Subjects: Q Science > QK Botany
Divisions: Faculty of Science, Technology and Environment (FSTE)
Depositing User: USP RSC Assistant
Date Deposited: 08 Jan 2018 09:48
Last Modified: 08 Jan 2018 09:48
URI: http://repository.usp.ac.fj/id/eprint/10370
UNSPECIFIED

Actions (login required)

View Item