Figure 1.

P. nigra PLC in relation to stem water potential. Data were fitted with a dose-response curve (solid line) in the form of PLC = min_PLC + (max_PLC − min_PLC)/(1 + (Ψ/EC₅₀)^slope), where min_PLC is minimum PLC in nonstressed plants (49.1%), max_PLC is 100%, EC₅₀ represents 50% loss of initial functionality [min_PLC + (max_PLC − min_PLC)/2], and slope is the rate of PLC increase at EC₅₀. The dashed lines represent the 95% confidence interval for the fit. PLC of plants recovering from stress was not used in the fitting procedure. [See online article for color version of this figure.]