Abstract: Tomatoes (Lycopersicon esculentum Mill.) were grown on a fine sandy soil using drip irrigation and
polyethylene mulch to evaluate the effects of irrigation scheduling on yield parameters. Under typical Souss
Massa production conditions. Capacitive sensors were used to automatically schedule irrigations. And twelve
irrigation treatments have been applied with a combination between three doses (50%, 75% and 100% ETC)
and frequencies (f=0.10, f=15% and f=20%).
The result of this study shows that irrigation dose and frequency doesn‟t affect fruits number in grafted tomato
plant (medium number =4.25 fruits/cluster); no significant effect on medium fruit size has been observed,
unlike each separate fruit size. However, irrigation have a moderate effect on total yield (reducing dose by
50%ETC generate a loss of 7% of yield). The effect of Irrigation frequency on yield doesn‟t exceed 2%.
Although, we can achieve the same performance with two completely different irrigation frequencies, this is
explained by the regulation of soil water content which is limiting the effect of irrigation frequencies.
According to our study we can confirm that irrigation scheduling can also control the size of marketable fruits.
Keywords: Tomato, green house, irrigation scheduling, dose, frequency, Yield.