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

摘要

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, grown 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. SWP and LWP were measured at midday using a pressure chamber. 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.