The Effect of Soil Management on Olive Yield and VOO Quality in a Rainfed Olive Grove of Central Spain

Abstract

Rainfed olive groves have been traditionally tilled in order to reduce the competition for water and nutrients. In sloping Mediterranean olive groves, this practice leads to high erosion rates, resulting in a reduction in soil fertility. Cover crops have been employed as a sustainable olive grove management strategy, but previous studies found differences in their effect on fruit load and there is scarce information on their influence on the virgin olive oil (VOO) quality. The aim of this study is to evaluate the effect of different soil management strategies on olive and oil yield and VOO physicochemical and sensory characteristics in a rainfed olive grove (238 trees·ha−1) of Cornicabra cultivar, the main in Central Spain. No effect of soil management was found in olive or oil yield along three cropping seasons. VOO quality was mainly influenced by the year, but slight differences were found in the driest year between the studied treatments. Small differences in fruit ripening, pigments, and several fatty acids as well as in sensory parameters were found.

Mycorrhizal, nutritional and virgin olive oil parameters affected by groundcovers

“…In contrast to our results, in a similar study area, Sastre et al. () did not find such marked differences between tillage (only one chisel pass) and GC. Instead, they found more differences between GC.…”

“…Regarding color, tillage treatment also differed from GC with lower values of luminosity (L*), which may be related to a higher content of pigments such as chlorophyll. In contrast to our results, in a similar study area, Sastre et al (2016) did not find such marked differences between tillage (only one chisel pass) and GC. Instead, they found more differences between GC.…”

“…Therefore, in these limited conditions, GC may decrease fruit yield in olive groves, at least in the initial years of GC establishment. However, yield reduction depends on the particular conditions of each year since GC had no impact on fruit yield in a 3‐year study under similar conditions ( Sastre et al., ).…”

“…Apart from AMF stimulation, several studies reported benefits from using GC in olive groves ( Palese et al., ), but very few have analyzed the connection with VOO parameters ( Gucci et al., ; Sastre et al., ). In this study, the effect of tillage on VOO clearly differed from that of GC use.…”

“…Consequently, these soils remain bare most of the year, suffering from soil erosion and low organic matter content and making them prone to particle and nutrient detachment (Gó mez et al, 2009;Gucci et al, 2012). In order to reduce sediment and nutrient loss and to increase soil fertility, vegetal groundcovers (GC) have been shown to be a good alternative to continuous tillage (Gonzalez-Sanchez et al, 2015;Sastre et al, 2017), although their effect on olive tree yield is controversial (Pardini et al, 2002;Sastre et al, 2016).…”