Gonçalves, AlexandreMartins, SandraSilva, ErmelindaBrito, CátiaPinto, LuísRocha, LuísPavia, IvoLuzio, AnaNunes, Fernando M.Rodrigues, M.A.Moutinho-Pereira, JoséCorreia, Carlos M.2019-02-012019-02-012018Gonçalves, Alexandre; Martins, Sandra; Silva, Ermelinda; Brito, Cátia; Pinto, Luís; Rocha, Luís; Pavia, Ivo; Luzio, Ana; Nunes, Fernando; Rodrigues, M.A.; Moutinho-Pereira, José; Correia, Carlos (2018). Fruit yield and quality of olives under different deficit irrigation strategies. In II Simpósio Internacional de Águas, Solos e Geotecnologias (SASGEO). Vila Realhttp://hdl.handle.net/10198/18618The Mediterranean Basin is a climate change hot spot where substantial warming and lower water availability is predicted. This scenario poses considerable challenges to olive groves, a crop with great ecological and socioeconomic importance. ln order to overcome these constrains, new cropping practices focusing on water use efficiency must be investigated. ln this work we aimed to investigate water management practices that can ensure the adequate compromise between yield and the quality of olive products. The study was conducted in Quinta do Prado, Lodões, Vila Flor (41 °20'13.3"N, 7°05'54.2"W) and a full irrigation (FI) control, applied daily, equivalent to 100% of crop evapotranspiration (ETc), was compared with three deficit irrigation strategies (DIS): regulated deficit irrigation (RDI; 80% of ETc in phases I and III of fruit growth and 10% of ETc in pit hardening stage, phase TI; 56 % of the ETc in all season), sustained deficit irrigation (SDI; 27.5% of ETc), and sustained deficit irrigation adopted by the farmer (SDIAF; 21.2% of ETc, applied weekly). The impact of treatments on fruit yield and quality during 2016 were evaluated. Using FI treatment as reference, no significant influence of RDI and SDI treatments were felt in crop yield, while the SDlAF treatment reduced it significantly (P<O.Ol ). Fruit quality analysis showed that the SDI treatment Ied to higher antioxidant activity than in FI and SDIAF treatments. However, the SDIAF strategy led to higher accumulation of both total phenols and flavonoids (P<O.Ol ). The fruit fat content was significantly higher in deficit irrigation treatments, when compared to the FI treatment. lrrigation treatments also induced changes in fruit fatty acids profile (P<O.OOl) since palmitoleic acid (C16:1) decreased in the deficit irrigation treatments, linoleic acid (Cl8:2) decreased in the SDIAF treatment, and linolenic acid (C18:3) decreased in RDI and SDI treatments. Except for SDIAF, despite the great disparity in the amount of water used among treatments, there were no significant differences in fruit production. Hence, with an increase of 30% in water consumption, changing from the SDlAF to the SDl treatment, this particular farmer can increase the orchard production, without losing fruit fat content and antioxidant capacity. This work gives new insights about the effect of DlS when used in olive orchards and might help to illustrate the sustainability of these management practices.engIrrigationOlive treeFruit yieldFruit qualityconference object