The sensitivity to water stress ofdifferentplant water indicators was evaluatedduring the latepostharvest period of extra-early nectarine trees growing in a commercial orchard and submitted to two irrigation treatments: (i) a control (TC), irrigated at 120% of crop evapotranspiration to avoid any soil water limita tions, and (ii) a water deficit treatment (TD), irrigated at 50% of TC. The plant indicators studied were: the maximum daily trunk shrinkage (MDS); trunk growth rate (TGR); midday stem water potential ( stem); leaf conductance (Gs); and net photosynthesis (Pn). Although the highest signal intensity (SI) values – the ratio of deficit irrigation treatment values to control values – were reached by TGR, Gs and Pn (2.6, 3 and 2.9, respectively), the sensitivity (S) values – calculated as the ratio of SI to coefficient of variation (SI CV−1) – were higher in stem and MDS (14 and 11.4, respectively), since their CV values were the lowest (11 and 14%, respectively). A new approach (S) is proposed to calculate the sensitivity of the plant water indicators, since the standard method can result in high sensitivity values without identifying differences between irrigation treatments. While S is more influenced by the CV values, S would be influenced by both the SI and CV values.