Cherry leafroll virus: Impact on olive fruit and virgin olive oil quality

Abstract

We performed a survey on the yield, quality, and chemical characteristics of virgin olive oils from two olive varieties in Croatian Istria: Frantoio and Ascolana tenera, on Cherry leafroll virus‐infected and virus‐noninfected trees and on two harvest dates. Free acidity, peroxide value, specific spectrophotometric absorptions at 232 and 270 nm, fatty acid composition, total phenols, o‐diphenols, oil color, and pigments were determined. Infected olives had lower oil yield and maturity index versus healthy ones. Oils from infected fruits had significant lower value of K232 and K270 and very elevated total phenols content compared to those obtained from healthy olives. Infected Frantoio gave a lower content of o‐diphenols than the healthy ones, which is in contrast to infected Ascolana that had higher values. The aim of this study is to determine the chemical changes in virgin olive oils from healthy and infected trees related to virus influence. According to our knowledge, this is the first survey on the possible influence of viruses on olive fruits, oil yield, and virgin olive oil quality.Practical applications: There are only few papers which analyze the influence of viruses on crops (especially influence on wine quality) and their effects on yield or other agronomic parameters. This work evaluates for the first time the impact of Cherry leafroll virus on the quality of virgin olive oil obtained from Frantoio and A. tenera varieties in terms of basic parameters related to the hydrolitic and oxidative status, content in antioxidant compounds, and in pigments as well as in fatty acid composition.

Impact of Olive Leaf Yellowing Associated Virus on Olive (Olea europaea L.) Oil

“…Moreover, CLRV induced negative effect on the 'Frantoio' oil quality, by lowering the amount of o-diphenols and the oleic/linoleic ratio. [27] A study carried out in Turkey, showed that SLRSV interfered negatively on yield, weight, and volume of olive fruit. It was determined values decreasing of mentioned fruit properties in virus-infected trees in comparison to non-infected trees.…”

“…A similar study accomplished to determine the effect of CLRV on two Italian cultivars grown in Croatian Istria (Frantoio and Ascolana), disclosed that the presence of this virus affects ‘Frantoio’ by decreasing the oil yield from 10.9% registered for the healthy olives versus 7.6% of the infected ones, while it does not interfere on ‘Ascolana’ oil yield. Moreover, CLRV induced negative effect on the ‘Frantoio’ oil quality, by lowering the amount of o ‐diphenols and the oleic/linoleic ratio …”

Establishment of a Sensitive qPCR Methodology for Detection of the Olive-Infecting Viruses in Portuguese and Tunisian Orchards

“…These symptoms are non-specific and difficult to recognize, and often occur in virus-infected olive trees without apparent symptoms, which makes viral diagnosis in the field impossible to perform (Martelli et al, 2002; Alabdullah et al, 2010; Martelli, 2011; Zellama et al, 2018). A decrease in oil yield and maturity index in virus infected olives was also reported, as well as elevated total phenols in olive oil content from infected olives when compared to healthy fruits (Godena et al, 2012). Nevertheless, the Olive leaf yellowing associated virus (OLYaV) was not found to have a negative interference in oil yield and quality (Fontana et al, 2019).…”

An integrated approach for understanding the high infection rates of olive viruses in Tunisia

“…Until now, 15 viruses have been identified in olive plants (Felix et al 2012), eight of them in Tunisia (Alabdullah et al 2009;El Air et al 2011). Some viruses have been recovered from asymptomatic trees and others with symptoms that include bumpy fruits, chlorosis, weakness or defoliation and reduction of yield and oil quality (Marte et al 1986;Castellano et al 1987;Alabdullah et al 2009;Cardoso et al 2009;Godena et al 2012).…”