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

Abstract

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. 

DOI:

Publication date: June 22, 2020

Issue: GiESCO 2019

Type: Article

Authors

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

Keywords

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

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

A 4D high resolution vineyard soil assessment for soil-hydrological interpretation in combination with automated data analysis and visualization to manage site-specific grape and wine quality

A Visual Information eNvironment for Effective agricultural management and Sustainability (VINES) is under development, which can provide significant competitive advantages to winegrowers by sustaining their appellation-specific grape and wine qualities and yields while measurably conserving water resources.

Influence of grapes origin and yeast strain on aroma profile of corvina and corvinone dry passito wines

Valpolicella is a wine region characterized by a wide use of the technology of grape drying for the production of two red passito wines, recognized as PDOs, “Recioto della Valpolicella” and the most famous “Amarone della Valpolicella”. Geographical origin of the grapes can influence wine composition by grape chemical composition yeast behaviour during fermentation. This study investigates the impact of different commercial yeast strains on aroma profiles of wines produced with withered grapes of different origins. In addition, the influence of spontaneous fermentation is also considered. METHODS: Experimental red wines were produced with a standard winemaking protocol with withered Corvina and Corvinone grapes obtained from two different geographical areas within the Valpolicella region. Fermentations were carried out with four different commercial yeasts plus a spontaneous fermentation. Wines were analysed by means of SPE- and SPME-GC-MS techniques and sensory analysis (sorting task).

Characterization of phenolics and VOCs in wines obtained from Malbec vineyards of the Uco Valley submitted to high-altitude solar UV-B and water restriction

Characterization of phenolics and VOCs in wines obtained from Malbec vineyards of the Uco Valley submitted to high-altitude solar UV-B and water restriction

Oligosaccharides from Vitis vinifera grape seeds: a focus on gentianose as a novel bioactive compound

AIM. Grape seeds (Vitis vinifera) are among the main constituents of grape pomace, also exploited in ingredients for nutraceutics and cosmeceutics, particularly regarding the phenolic fraction. The macromolecules of grape/wine include polyphenols, proteins and polysaccharides.

Late frost protection in Champagne

Probably one of the most counterintuitive impacts of climate change on vine is the increased frequency of late frost. Champagne, due to its septentrional position is historically and regularly affected by this meteorological hazard. Champagne has therefore developed a strong experience in frost protection with first experiments dating from the end of 19th century. Frost protection can be divided in two parts: passive and active. Passive protection includes all the methods that do not seek to modify the vine’s environment or resistance at the time of frost. The most iconic passive protection in Champagne is the establishment of the individual reserve. This reserve allows to stock a certain quantity of clear wine during a surplus year to compensate a meteorological hazard like frost during the following years. Other common passive methods are the control of planting area (walls, bushes, topography), the choice of grape variety, late pruning, or the impact of grass cover and tillage. Active frost protection is also divided in two parts. Most of the existing techniques tend to modify vine’s environment. Most of the time they provide warmth (candles, heaters, windmills, heating cables…), or stabilise bud’s temperature above a lethal threshold (water sprinkling). The other way to actively fight is to enhance the resistance of buds to frost (elicitors). The Comité Champagne evaluates frost protection methods following three main axes: the efficiency, the profitability, and the environmental impact through a lifecycle assessment. This study will present the results on both passive and active protection following these three axes.