Three main questions have to be answered for optimizing irrigation: how much, when and how. The last one, dealing with the design and characteristics of the irrigation system, is not addressed in this work; just to remark that localised irrigation is the best solution for most olive orchards, and that drippers are usually more convenient than microsprinklers. The second question cannot be properly answered without taking into account the time evolution of the crop water needs, which bring us to the first question: the optimum irrigation amount (IA) for our olive orchard. This work starts with an overview of the crop coefficient approach for calculating the required IA to replace the crop water needs, from the FAO recommendations to recent improvements that reduce the empiricism of the involved coefficients. At this point, aspects on the irrigation both of young and highly density orchards are commented. Deficit irrigation strategies are then discussed, with a comparison between regulated deficit irrigation and partial rootzone drying, plus a mention to old practices such as supplementary or complementary irrigation, that could be adequate in some cases; the section ends with practical considerations on the soil volume wetted by irrigation. An overview on the most promising techniques for scheduling irrigation occupies the rest of this work; most attention is dedicated to those based on plant measurements, namely plant water potential, sap flow and trunk diameter variations. Finally, the potential of thermal sensing combined with plant measurements for scheduling irrigation in commercial orchards is outlined.

14 páginas, 3 figuras, 3 tablas, 47 referencias.-- OliveBioteq 2nd edition. special Seminars and Invited lectures.-- Celebrado del 5-10 de noviembre 2006, en Marsala-Mazara del Vallo, Italia.

Peer reviewed