What question did this study set out to answer?

Evaluate the impact of different deficit irrigation strategies on the physiological and productive responses of a young super high-density olive orchard.

June 15, 2026Open Access

Deficit irrigation in a young, super high-density hedgerow olive orchard (cv. Arbosana): effects on physiological, vegetative, and productive parameters

Key Points

Evaluate the impact of different deficit irrigation strategies on the physiological and productive responses of a young super high-density olive orchard.
Evaluated three deficit irrigation (DI) treatments: sustained DI at 70% ETc, and regulated DI at 50% and 25% ETc, compared to control at 100% ETc.
Measurements taken over three productive seasons to assess vegetative and yield parameters.
Water savings calculated for each treatment.
Continuous DI (CDI70) significantly increased fruit and oil yield compared to control.
Regulated DI treatments (RDI50 and RDI25) led to reduced yields, particularly in the second crop cycle.
Overall, continuous DI improved water productivity and maintained balanced water status.

Abstract

Over the past three decades, super high-density (SHD) olive orchards (1000 trees ha⁻¹) have been widely implemented for olive ( Olea europaea L.) cultivation. These systems enable early entry into production and full mechanization, but require high-water supply and they do not tolerate prolonged water stress. These latter aspects represent a challenge for arid growing areas such as those in western Argentina. This study evaluated several productive, vegetative and physiological responses to deficit irrigation (DI) strategies in a young SHD orchard (cv. Arbosana). Measurements were made during the first three productive seasons. Three DI treatments - one sustaining DI at 70% ETc throughout the entire growth period evaluated (CDI70), and two regulated DI treatments applying 50% and 25% of ETc (RDI50 and RDI25, respectively) during non-critical periods - were compared against a control (100% ETc) treatment. The total irrigation water savings were 30% (CDI70 and RDI50) and nearly 50% (RDI25). No clear differences in vegetative parameters were found between the different DI treatments, and between these and the control treatment. In contrast, fruit yield parameters showed a marked effect of the different DI treatments on alternate bearing of the olive crop. This was particularly noticeable for the two regulated DI treatments, in which a significant decline in yield was observed in the second crop cycle. Differently, the continuous DI treatment (CDI70), besides maintaining a balanced water status, was able to sustain and significantly increase fruit and oil yield at the end of the third crop cycle. In this latter treatment - considering the cumulative results of the three cycles examined - those yield parameters also showed significantly higher values than those from the control treatment. As a result of lower water consumption and higher yields, water productivity was also significantly enhanced. Because of major effects on fruit bearing, moderate or severe water restrictions (RDI50 and RDI25 treatments) would not be viable for sustaining production of 'Arbosana' trees in SHD systems. Although the results must be validated in longer trials, continuous DI (70% ETc during the entire crop season) could moderate vegetative growth and increase productivity in a sustained manner.

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