Different Quantities of Applied Water on <i>Olea europaea</i> L. Cultivated under Humid Conditions

Abstract

Due to increased occurrence and intensity of agricultural droughts in humid Mediterranean regions, monitored irrigation is becoming an increasingly inevitable element of agricultural practice. To determine the impact of different irrigation regimes on olive tree (Olea europaea L.) growth and crop yield, and of the olive oil production and biophenol content, a 3-year study was conducted in an olive grove located in a relatively humid region of southwestern Slovenia. The mean olive production from trees under full irrigation (replacement of 100% crop evapotranspiration) was significantly higher than those that were only rain fed or were under deficit irrigation (replacement of 33 and 66% crop evapotranspiration). There were no significant differences in total biophenol contents of the olive oil across these irrigation treatments. These irrigation effects can be explained according to the levels of precipitation throughout the growing season. Despite the positive effects of rainfall on these parameters, the mean olive oil yield of the rain-fed olives was about 30% lower than that for the deficit irrigation treatments.