Abstract
This study reports experimental evidence on the effect of short-term potassium fertilization on potassium uptake, tissue concentration and hydraulic conductance of pot-grown laurel plants. Potassium uptake and loading into the xylem of laurel seedlings increased within 24 h after fertilization. Potassium was not accumulated in roots and leaves, but the [K(+)] of xylem sap was 80% higher in fertilized plants (+K) than in potassium-starved plants (-K), as a likely result of recirculation between xylem and phloem. Increased xylem sap [K(+)] resulted in a 45% increase in transpiration rate, a 30% increase in plant hydraulic conductance (K(plant)) and a 120% increase in leaf-specific conductivity of the shoot (k(shoot)). We suggest that this increase was due to ion-mediated up-regulation of xylem hydraulics, possibly caused by the interaction of potassium ions with the pectic matrix of intervessel pits. The enhancement of hydraulic conductance following short-term potassium fertilization is a phenomenon that can be of advantage to plants for maintaining cell turgor, stomatal aperture and gas exchange rates under moderate drought stress. Our data provide additional support for the important role of potassium nutrition in agriculture and forestry.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
