A greenhouse tomato (Lycopersicon esculentum Mill.) cultivar trial was conducted at the experimental farm of
Tbhirine in Souss Massa Region (AGADIR). In this study the tolerance of tomato varieties to irrigation turn in
soilless culture was evaluated. Four varieties of grape tomato were being used (Colby, Delica, Granit and Pitenza).
Tree irrigation turns used in this study were (T1: Normal Irrigation Turn, T2: minus -1 irrigation, T3: minus -2
irrigations) and treatments were randomly distributed according to RCBD, with three replications. Varieties were
affected differently by water stress, but, in the early growth stage no significant difference was observed. After the
3rd week of trial, Colby variety provides the best agronomic parameters regarding the apex elongation and stem
diameter. However, Production parameters revealed that Pitenza and Delica varieties gave more flowers per plant
(134-108 Flow/Plt) for a normal irrigation scheduling and (105 Flow/Plt) in water stress conditions. In fact, water
deficit improve fruit number per plant, and accelerate fruit maturity from 0 to 5 fruits /week.