Calcium in plants: control problems associated with a diversity of roles

Plants often grow in soils with a high content of calcium, some of which enters the roots to be transported through the xylem in the transpiration stream. The need for large amounts of calcium for structural and other purposes has long been recognised, but during the last decade evidence has accumul...

Full description

Saved in:
Bibliographic Details
Published in:Science progress (1916) 1993-01, Vol.77 (3/4), p.233-251
Main Authors: De Silva, D.L.R., Mansfield, T.A.
Format: Article
Language:English
Subjects:
Animal cells
Calcicoles
Calcifuges
Calcium
Guard cells
Plant cells
Plants
Signal transduction
Transpiration
Xylem
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Plants often grow in soils with a high content of calcium, some of which enters the roots to be transported through the xylem in the transpiration stream. The need for large amounts of calcium for structural and other purposes has long been recognised, but during the last decade evidence has accumulated that calcium ions also function as second or subsequent messengers in plant cells. A great deal of the available information relates to stomatal guard cells, and in particular their response to the stress hormone abscisic acid (ABA). Although the precise position of calcium in the signal transduction sequence is still unresolved, there is now little doubt that a rapid elevation of cytosolic calcium occurs in guard cells when ABA arrives at the outer surface of the plasma membrane. This elevation is of the order of a few mmol m⁻³ , but the concentrations of calcium ions transported into leaves in xylem sap are 1,000 times higher than this. A major dilemma for the plant is to prevent such high calcium concentrations from reaching the stomatal apparatus. New information suggests that genotypes that are tolerant or intolerant of soil calcium (calcicoles and calcifuges) may differ considerably in their capacity to regulate the distribution of calcium within the plant.
ISSN:0036-8504
2047-7163