GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Impact of grapevine leafroll virus infections on vine physiology and the berry transcriptome

Impact of grapevine leafroll virus infections on vine physiology and the berry transcriptome


Context and purpose of the study ‐ Grapevine leafroll associated virus (GLRaV) infections deteriorate vine physiological performance and cause high losses of yield and fruit quality and are thus causing serious economic losses in the wine industry. Physiological and molecular studies on the impact of leafroll infections on plant and fruit metabolism are relatively scare and the molecular mechanisms associated with the plant response to the virus during berry ripening are not well understood so far. Commonly observed phenotypic alterations consist in a ripening delay, a reduction in anthocyanin and sugar accumulation. The few molecular studies associated in particular the lack of anthocyanin of berries of infected vines to a repression of key genes of anthocyanin biosynthesis. However such studies did never account for berry heterogeneity and potential phenological shifts induced by virus infection, which could have introduced biases in gene expression studies.

Material and methods ‐ In the present study a long‐term experiment was established in the year 2000, with the aim to investigate the effects of infections with different GLRaVs (GLRaV 1 & GLRaV 1+3) on vine and grape physiology. Physiological data (yield, vigor, photosynthesis, berry quality) has been collected from 2015 to 2018. In 2018 a transcriptomic (RNA‐seq) analysis of 2 reconstituted berry ripening stages was performed. Therefore 245 berries were individually sampled and individually analyzed for sugar and organic acids in order to re‐constitute 2 homogenous ripening stages to circumvent intercluster berry heterogeneity and thus to compensate for phenological shifts induced by virus infections. RNA of reconstituted samples was extracted and sequenced by single end sequencing and subsequently analyzed for differentially expressed genes (DEGs).

Results ‐ Physiological measurement showed a significant decrease in photosynthesis, yield and sugar content, which were highly significant in the co‐infected vines (GLRaV 1+3). RNA‐sequencing of berries revealed a total of 2136 DEGs between control and virus infections. Several transcriptions factors related to abiotic and biotic stress could be identified and showed interesting variation in dependence to ripening stage and infection severity. Strikingly previously reported repression of the anthocyanin biosynthesis and sugar metabolism could not be confirmed by gene expression. This illustrates that the main damaging effect on GLRaV infection is rather related to a phenological shift than to a direct impact on metabolism. The here reported results give new insight in the mechanism of leafroll infection and emphasize the importance of the sampling protocol of molecular studies investigating berry metabolism. 


Publication date: June 22, 2020

Issue: GiESCO 2019

Type: Article


Markus RIENTH (1), Sana GHAFFARI (1,2), Jean‐Sébastien REYNARD (3)

(1) Changins, haute ecole de viticulture et œnologie, route de Duillier 50, 1260 Nyon, Switzerland
(2) Higher Institute of Applied Biology of Medenine, Route el Djorf km 22.5, 4119 Medenine, Tunisia
(3) Agroscope, route de Duillier 50, 1260 Nyon, Switzerland

Contact the author


Grapevine leafroll virus, GLRaV 1, GLRaV 3, RNA‐seq, berry metabolism


GiESCO 2019 | IVES Conference Series


Related articles…

Water and physiological response to early leaf removal of cv. Verdejo in rainfed conditions, at different times of the day, in the D.O. Rueda (Spain)

Aim: Early leaf removal, generally applied before flowering, is mostly conceived as a technique to control grape yield and improve the health of grapes and focused on the final objective of increasing wine quality.

Modeling sugar accumulation dynamics of a wide variety of grape cultivars (Vitis vinifera L.)

Climate change is a major challenge in wine production. The IPCC (2014) projected that by the end of the 21st century average temperatures will increase by 1-3.7°C. Consequently, harvest dates could advance by approximately 30 days. A general observed trend is the increase in berry sugar content and decrease in organic acids, posing challenges for winegrowers. Variability among cultivars is a precious resource to adapt viticulture to a changing environment.

Copper reduction strategy for sangiovese in organic viticulture

Organic viticulture requires copper based treatments for bunch protection even though an intensive employment is no longer admitted because of its low leaching and phytotoxicity in the soil. UE Reg. 1981/2018 set copper employment to 4 kg/ha for year or 28 during 7 years with an absolute level allowed of 6 Kg/ha although those limits were decreased frequently.

Vitamins in grape must: let’s lift a corner of the veil

Although vitamins stand as major actors to yeasts prime metabolic pathways, their significance in oenology and winemaking remains rather obscure nowadays, having been mostly unexplored for several decades.

Un Système d’Informations à Références Spatiales sur le Vignoble. Un outil performant d’aide aux recherches sur la caractérisation des terroirs viticoles

The “Terroirs d’Anjou” project led by the Agronomy sector of the Vine and Wine Research Unit of the INRA center in Angers aims to characterize the viticultural terroirs in a study area which includes 29 municipalities in the Maine et Loire and cuts across the Anjou, Coteaux du layon and Coteaux de l’Aubance appellation areas.