Evaluation of polyethylene glycol test for measurement of cell membrane stability in maize

Abstract

Cell membrane stability (CMS) of three maize (Zea mays L.) cultivars was determined by the polyethylene glycol (PEG) test at different leaf positions and compared with other physiological measurements to clarify the mechanism of the PEG test. Percentage injury in the PEG test was well correlated with the leaf water potential, osmotic potential, leaf thickness, and Ca and Mg concentrations in the leaf tissues and cell sap. It was comparable with the cuticular resistance but did not show any relationship with stomatal resistance. Osmotic potential of leaf tissues may affect the desiccation treatment in the PEG solution. Sugars, K, and Ca were the major contributors to the osmotic potential. Relative contribution of K to the osmotic concentration was higher than that of sugars in maize. Percentage injury in the PEG test was influenced mainly by the osmotic potential, leaf thickness, and Ca and Mg concentrations of leaf tissues.