CSIRO Publishing blank image blank image blank image blank imageBooksblank image blank image blank image blank imageJournalsblank image blank image blank image blank imageAbout Usblank image blank image blank image blank imageShopping Cartblank image blank image blank image You are here: Journals > Australian Journal of Botany   
Australian Journal of Botany
Journal Banner
  Southern hemisphere botanical ecosystems
blank image Search
blank image blank image
blank image
  Advanced Search

Journal Home
About the Journal
Editorial Structure
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Turner Review Series
Sample Issue
For Authors
General Information
Submit Article
Author Instructions
Open Access
Awards and Prizes
For Referees
Referee Guidelines
Review an Article
Annual Referee Index
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates
Library Recommendation

blue arrow e-Alerts
blank image
Subscribe to our Email Alert or RSS feeds for the latest journal papers.

red arrow Connect with us
blank image
facebook twitter logo LinkedIn

red arrow PrometheusWiki
blank image
Protocols in ecological and environmental plant physiology


Article << Previous     |     Next >>   Contents Vol 38(1)

Xeromorphic Leaves of Hakea suaveolens R. Br. IV. Ontogeny, Structure and Function of the Sclereids

HS Heide-Jorgensen

Australian Journal of Botany 38(1) 25 - 43
Published: 1990


Osteosclereids in the leaves of Hakea suaveolens are investigated from a developmental, structural and functional point of view. The sclereid initial cell is located outermost in a boundary parenchyma comprising 1-3 cell layers next to the palisade tissue. Boundary parenchyma cells, including sclereid initial cells, are the first cells to accumulate starch. Acid phosphatase was localised during development of sclereids and palisade cells. The outer ramifications of the sclereid form a pseudohypodermis, and the inner ramifications penetrate 1-3 cell layers inwards, making contact with specialised cells (tracheoids) of the vein endings and with fibres. The sclereids do not become lignified in the outer ramifications, and they remain alive as long as the leaf itself. Water pathways were localised by addition of the fluorochrome berberine sulfate to the transpiration stream. It is concluded that, besides giving mechanical strength, the sclereids are also important as vein extensions and that, like bundle sheath extensions, they conduct water to the epidermis and directly to both palisade layers. The percentage of the cross-sectional leaf area occupied by lignified water-conducting cells, including sclereids, is higher than in many other cylindrical, xeromorphic leaves. There are about 200 sclereids per square millimetre of palisade tissue in sun leaves, but the number falls in shade leaves and after fertilisation with nitrate and phosphate.

Full text doi:10.1071/BT9900025

© CSIRO 1990

blank image
Subscriber Login

PDF (1.7 MB) $25
 Export Citation
Legal & Privacy | Contact Us | Help


© CSIRO 1996-2016