Relationships between xylem sap constituents and leaf conductance of well-watered and water-stressed maize across three xylem sap sampling techniques

Abstract

Many different techniques have been used for xylem sap collection, but few direct comparisons of techniques have been conducted and few comparisons have been based on comprehensive analyses of xylem sap. Moreover, the suitability of extraction techniques for use on plants grown under water-stress conditions has not been addressed. Xylem sap was extracted from both well-watered and water-stressed Zea mays plants using three different techniques. The main aim was to determine how the extraction method altered the correlations between sap constituents and stomatal conductance in order to determine which relationships change with extraction technique. A 'root pressure' technique was the simplest..