The Impact of Irrigation on Olive Fruit Yield and Oil Quality in a Humid Climate

Abstract

The expansion of olive orchards into regions with no tradition of olive production and humid climates, such as Uruguay, with more than 1200 mm of annual rainfall, calls into question the need for irrigation. In these regions, however, years with water deficit during summers are quite common. The vapor pressure deficit during summer is lower than in countries with a Mediterranean climate. The high variability in interannual water availability in the current context of climate change, with a growing tendency for extreme events to occur, emphasizes the need to evaluate the production response of olive trees to irrigation. To achieve this, three irrigation treatments were applied to Arbequina and Frantoio cultivars according to the value of the maximum crop evapotranspiration: a first treatment applying 100% ETc, corresponding to being fully irrigated; a second treatment applying 50% ETc; and a third treatment in which neither irrigation nor rain inputs occurred from the end of the pit hardening period until harvest. Results show the possibility of an increasing fruit weight and pulp/pit ratio through irrigation in the local environmental conditions. The oil content in response to irrigation was different within cultivars. Water restriction conditions did not affect the oil content of olives in Arbequina, while in Frantoio it increased it. Polyphenols in fruit increased under water stress for both cultivars. The technological applicability of the results obtained must be accompanied by an economic analysis. The results obtained highlight the need for better use of irrigation water during the growth and ripening phase of the olive fruit under a humid climate.

Combining Zeolites with Early-Maturing Annual Legume Cover Crops in Rainfed Orchards: Effects on Yield, Fatty Acid Composition and Polyphenolic Profile of Olives and Olive Oil

“…Beyond the olive tree genotype and the incidence of pests and diseases, the total fat content and fatty acid composition are influenced by many factors, including olives’ ripening stage, fruit biometry traits (e.g., fruit weight and pulp-to-pit ratio), fruit moisture, crop load and multiple agronomic and environmental conditions that affect, among other aspects, the plant water, nutritional status and light environment around the canopy [ 1 , 8 , 42 , 47 , 48 , 49 , 50 ]. Table 7 shows higher total fat content in both the LC and ZL treatments in 2018, while in 2019, the behavior was diametrically opposite.…”

Influence of Cultivar on Nutritional Composition and Nutraceutical Potential of Pecan Growing in Uruguay

“…The specific soil depth and slow water infiltration combined with a very irregular rain pattern submits plants to different stresses (excess and deficit), ( 5 ) which could be of key importance to promote secondary metabolism and the obtention bioactive compound in nuts. In a recent study at the same location, our group set experiments to study the impact of clime, soil, and irrigation management in olive fruits chemical composition ( 46 ). Similar research approach could be useful to understand mechanisms and determine thresholds for pecan bioactive compounds accumulation.…”