Physiological indicators of plant water status as criteria for irrigation scheduling in table grapes cv. Crimson Seedless, irrigated by drip

Several physiological indicators of plant water status (stem water potential, SWP, leaf water potential, LWP and trunk growth rate, TGR,), were tested as criteria for irrigation scheduling in table grapes cv Crimson Seedless, growing, in a deep (2 m) clay loamy soil, at the Aconcagua Valley, Chile. Four irrigation treatments were applied: T1; 100% of crop evapotranspiration (Etc), T2, 75% of Etc, T3, 50% of Etc, all over the season, and T4, with a variable amount of water (between 0 to 100% of Etc) all over the season. Stem water potential (SWP) and leaf water potential (LWP) were measured at midday using a pressure chamber. Trunk growth rate (TGR) was measured continuously with an electronic dendrometer. Soil water changes were also measured. The first year results shows that TGR was most sensitive than the other two indicators, however, the interaction between plant phenology and trunk growth must be considered.