Réponse de l'olivier à la technique de dessèchement partiel des racines durant trois années consécutives d'essai

Olive Tree Response to Partial Root Drying during Three Consecutive Years. Water scarcity appears as one of the main factors limiting agricultural development. For this reason it is necessarily to reduce water use for irrigation and thereby increasing crop water use efficiency. This experiment have lead to development of different irrigation practice (partial root drying and regulated deficit irrigation) which aims to study these effects on water use efficiency in olive trees under semi arid climate of Tunisia. The experiment was done during three consecutive years in a drip irrigated orchard of "Chetoui" the most important cultivar of north of Tunisia. Five irrigation treatments were applied: Rain fed (without irrigation), 100%PRD and 50%PRD (Respectively 100% and 50% of dose on one side alternating the wetted and dried sides of the root system every ten days) and 100%ETc and 50%ETc (respectively 100% and 50% of dose on both sides). Results showed that irrigation slightly affected yield and differences between treatments were no significant especially in the last year of the experiment except the rainfed. Ripening index measurement given that it increased with the increase of water deficit but the oil yield was unaffected. Also, results showed that vegetative growth was reduced by water deficit.