How does sharka affect the phenolics of plum fruit (Prunus domestica L.)?

Abstract

Plum pox virus (PPV), the causal agent of the sharka disease, is the most important viral disease in plums. To understand plant defense response against PPV-infection, changes in the composition of phenolics were studied in plum fruit (Prunus domestica L.). The phenolics were determined in visually undeformed and necrotic tissue during the last three ripening stages. The results indicated a significantly modified composition of anthocyanins, flavonols and hydroxycinnamic acids, in necrotic tissue the most. The phenolics differed significantly also between developmental stages and give insight into the phenolic profile of fallen unripe fruit. This study shows how PPV infection induces the biosynthesis of flavonoids in plum fruit.

Deciphering Prunus Responses to PPV Infection: A Way toward the Use of Metabolomics Approach for the Diagnostic of Sharka Disease

“…In summary, PPV infection seems to produce an earlier fruit ripening [37,38,41], which may also have an effect on primary compounds such as the soluble solids content, sugars, and organic acids and, consequently, on the fruit quality. These parameters are described below.…”

“…Therefore, this part of the review focuses on the modifications induced by PPV infection in Prunus fruits. While the main studies concerned plum trees [35][36][37][38], here, we also present relevant studies on apricot trees [39] and peach trees [40].…”

“…PPV infection altered the maturation process. Long-term infected fruits had a lower ripening index [39] and a sour taste and were more acidic than fully ripened healthy fruits on day 30 [37,38,40]. Premature fruit dropping thus yields fruits with an inferior taste for both plums and apricots.…”

“…Two main studies explored the modification of phenolic compounds induced by PPV infection in plums [36,38]. In both studies, the effect of PPV-Rec on healthy versus infected trees was studied during the last 3 weeks of ripening.…”

“…Usenik et al [36] also sampled healthy trees at day 30 and conducted an experiment with infected trees that displayed different durations of infection: short-term infected trees (at least 1 year) versus long-term infected trees (at least 5 years). In the other study, Usenik et al [38] analyzed infected trees with a unknown duration of infection by using visually undeformed and necrotic fruit tissues. Nevertheless, infected trees displayed similar symptoms to long-term infected trees, with strong symptoms on the leaves and fruits and a similar level of premature fruit dropping.…”