An index from sap flow records to schedule irrigation in super-high density olive orchards

Regulated deficit irrigation (RDI), recommended for super-high density (SHD) olive orchards, requires a precise control of irrigation. Water must be supplied on the phenological stages when the plant is most sensitive to water stress, but irrigation promotes plant vigour, and excessive growth hampers management in SHD orchards. A reliable water stress indicator is needed, therefore, for the proper management of RDI. Here we present an evaluation of the performance of DEp, an index previously reported by Cuevas et al. (2012). The index is derived from sap flow measurements in RDI trees and in fully irrigated trees used as a reference. We evaluated the index during the irrigation seasons of 2011 and 2012, in an ‘Arbequina’ olive orchard with 1667 trees ha-1 close to Seville, southwest Spain. The index showed a potential for scheduling RDI strategies, although its reliability decreased on periods of fluctuating atmospheric demand. The required data analyses and data interpretation make the DEp index suitable for well-trained users only.España: Ministry of Science and innovation AGL2009-11310/AGRJunta de andalucía AGR-6456-201

A regulated deficit irrigation strategy for hedgerow olive orchards with high plant density

Background & Aims There is not a consensus on the best irrigation approach for super-high density (SHD) olive orchards. Our aim was to design and test a regulated deficit irrigation (RDI) strategy for a sustainable balance between water saving, tree vigour and oil production. Methods We tested our RDI strategy for 3 years in an ‘Arbequina’ orchard with 1,667 trees ha−1. Two levels of irrigation reduction were applied, 60RDI and 30RDI, scaled to replacing 60 % and 30 %, respectively, of the of irrigation needs (IN). We also had a full irrigation (FI) treatment as control, with IN totalling 4,701 m3 ha−1 Results The 30RDI treatment showed the best balance between water saving, tree vigour and oil production. With a yearly irrigation amount (IA) of 1,366 m3 ha−1, which meant 72 % water saving as compared to FI, the reduction in oil yield was 26 % only. Conclusions Our results, together with recent knowledge on the effect of water stress on fruit development, allowed us to suggest a potentially improved RDI strategy for which a total IA of ca. 2,100 m3 ha−1 was calculated. Both some management details and the benefits of this suggested RDI strategy are still to be tested

Steps toward an improvement in process-based models of water use by fruit trees: a case study in olive.

International audienc

Using a process-based stomatal model in olive and its potential application to deficit irrigation studies.

International audienc