An Improved Method for Using Electrolyte Leakage to Assess Membrane Competence in Plant Tissues

Abstract

A new expression for ion leakage from plant tissue, the tissue ionic conductance (gT), is compared with electrical conductivity (EC) and a commonly used damage index (Id) to test the ability of each expression to correctly describe leakiness in two model systems representing examples of physiological processes with well-known effects on membrane permeability. In experiments in which drought-acclimated leaves were compared with nonacclimated leaves and senescing leaves were compared with nonsenescing leaves, Id contradicted our expectation that acclimated tissue would be less leaky than nonacclimated tissue, and gT1and EC confirmed this expectation. In a comparison of senescing and nonsenescing tissue, Id again contradicted our expectation that senescing tissue would be more leaky than nonsenescing, and EC and gT, were confirming. Using a diffusion analysis approach, we show that Id fails to account for variation in the concentration gradient between the tissue and the bathing solution and variation in the surface area through which efflux occurs. Furthermore, because Id is a parameter that relates treatment performance to control performance as a percentage value, it distorts the actual differences among treatments. The resulting artifacts lead to a presentation of membrane integrity which is probably incorrect.EC is a more direct measurement of net ion efflux and appears to be less vulnerable to artifact. However, because gTi is the only expression that explicitly includes chemical driving force and tissue surface area, it is the most reliable of the three expressions.Measuring solute leakage from plant tissue is a long-standing method for estimating membrane permeability in relation to environmental stresses, growth and development, and genotypic variation. Early published accounts used total electrolyte leakage, expressed as specific conductance (EC2) of the aqueous bathing solution in which the tissue was immersed, to indicate degree of damage resulting from chilling injury (3,4)

Physical and metabolic alterations in "Prata Anã" banana induced by mechanical damage at room temperature

“…The electrolyte leakage was determined using the methodology described by Whilton et al (1992), by which a piece (diameter 1 cm) of damaged peel per fruit is removed. This section was washed in distilled water and surface-dried on absorbent paper, and then incubated for 2 hours in a test tube with lid, containing 18 mL of distilled water and maintained at room conditions.…”

The OsMYB30 Transcription Factor Suppresses Cold Tolerance by Interacting with a JAZ Protein and Suppressing β-Amylase Expression

“…2B). It has been known that electrolyte leakage could reflect the damage of cell membranes, and the maintenance of cell membrane integrity and stability has been reported as a major contributing factor for cold tolerance (Whitlow et al, 1992;Morsy et al, 2005). Therefore, we examined the electrolyte leakage of the overexpression plants and ZH11 during cold stress conditions.…”

“…Another study suggested that maltose could protect the photosynthetic electron transport chain during cold stress treatment Guy, 2004, 2005). It has been generally accepted that the maintenance of cell membrane integrity and stability is critical for cold stress tolerance (Whitlow et al, 1992;Morsy et al, 2005), and conductivity can directly reflect damage to the cell membrane. Our results showed the relevance between maltose content and conductivity during cold stress treatment (Figs.…”

The Ethanol Dip and Vapor Delays Chilling Injury of Cucumber (Cucumis Sativus L. cv. Ceylan), During Storage.

“…In the present study, no CI symptoms seen until 10th day of storage, but at the day 15, CI symptoms started in all treatments, however, the cucumbers in D800 and D1600 treatments have less CI scores than the other treatments. Electrolyte leakage can be used to determine changes in membrane permeability caused by environmental stress factors such as CI [27,28]. It is therefore a useful method is measurement the K ion leakage for determining chilling damage, and it has been reported that in cucumbers, an increase in ion leakage is associated with cell damage caused by CI [29,30,31]).…”