GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Early detection project – make a GTD infection visible without disease symptoms

Early detection project – make a GTD infection visible without disease symptoms

Abstract

Context and purpose of the study ‐ The presence of grapevine trunk diseases (GTDs) related pathogens leads to severe economic losses in wine‐growing regions all over the world. GTDs cause foliar discoloration, stunted growth, decline, sectorial and/or central necrosis of the trunk wood, and dieback, while the quality and the quantity of the grapes and therefore the wine production is reduced. The disease management is challenging for vine‐growers since the responsible fungi colonize wood tissues (and are therefore inaccessible for conventional fungicides) and the related symptoms occur mostly after a long period of latency. The aims of this project were first to distinguish between healthy and infected plants before the symptoms appear and second to document the efficacy of BASF ´s Tessior®‐ System for wound protection under field conditions.

Material and methods ‐ Long term field trials were established between 2014 and 2015 in Germany, France, Greece, and Italy, where each year the pruning wounds are treated with Tessior®. In order to increase the infection pressure, some of the vineyards are artificially inoculated with spores of Phaeomoniellachlamydospora and Botryosphaeriaceae species. The presence of P. chlamydospora – a pathogen causing esca‐disease – and Botryosphaeriaceae species – causing Botryosphaeria dieback – in grapevines was determined with an optimized protocol. Samples were collected by drilling a 5 mm diameter hole in the spurs below a pruning wound which was closed then with a wound sealant. The wood chips were lyophilized and afterwards homogenized using TissueLyser II (Qiagen). Total genomic DNA was extracted from the grapevine samples and quantitative Real‐Time PCR using TaqMan probes was performed.

Results ‐ This protocol has been proved to be fast and accurate to quantify the DNA amount of GTDs related pathogens in grapevine wood. Furthermore, the efficacy of Tessior® wound protectant has been verified showing significant reduction of infection with P. chlamydospora and Botryosphaeriaceae species.

DOI:

Publication date: June 22, 2020

Issue: GiESCO 2019

Type: Article

Authors

Szabina LENGYEL (1), Randall E. GOLD (2), Jochen FISCHER (1), Alexander YEMELIN (1), Eckhard THINES (1), Annett KÜHN (2)

(1) Institut für Biotechnologie und Wirkstoff-Forschung gGmbH, Erwin-Schrödinger-Straße 56, D-67663 Kaiserslautern, Germany
(2) BASF SE, Agricultural Center, Speyerer Straße 2, D-67117 Limburgerhof, Germany

Contact the author

Keywords

Grapevine, Phaeomoniellachlamydospora, Botryosphaeriaceae, quantitative Real‐Time PCR, TaqMan, Tessior®

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

The effect of wine cork closures on volatile sulfur compounds during accelerated post-bottle ageing in Shiraz wines

Reduced off-flavour is an organoleptic defect due to an excess of volatile sulfur compounds (VSC) in wine and often happening in Shiraz wines. This off-flavour is a direct consequence of the lack of oxygen flow during winemaking and bottle storage. Therefore, wine closure could have a direct impact on the formation of VSC due to the oxygen transfer rate that can modulate their levels. Even if dimethylsulfide (DMS) contributes to reduced off-flavor, it is also a fruity note enhancer in wine and its evolution during wine ageing is not well understood.

Impact of yeast derivatives to increase the phenolic maturity and aroma intensity of wine

Using viticultural and enological techniques to increase aromatics in white wine is a prized yet challenging technique for commercial wine producers. Equally difficult are challenges encountered in hastening phenolic maturity and thereby increasing color intensity in red wines. The ability to alter organoleptic and visual properties of wines plays a decisive role in vintages in which grapes are not able to reach full maturity, which is seen increasingly more often as a result of climate change. A new, yeast-based product on the viticultural market may give the opportunity to increase sensory properties of finished wines. Manufacturer packaging claims these yeast derivatives intensify wine aromas of white grape varieties, as well as improve phenolic ripeness of red varieties, but the effects of this application have been little researched until now. The current study applied the yeast derivative, according to the manufacture’s instructions, to the leaves of both neutral and aromatic white wine varieties, as well as on structured red wine varieties. Chemical parameters and volatile aromatics were analyzed in grape musts and finished wines, and all wines were subjected to sensory analysis by a tasting panel. Collective results of all analyses showed that the application of the yeast derivative in the vineyard showed no effect across all varieties examined, and did not intensify white wine aromatics, nor improve phenolic ripeness and color intensity in red wine.

Decline of rootstock-mediated physiological responses in Tempranillo grapevines by prolonged extreme conditions

Agriculture faces many global warming challenges especially in the Mediterranean region. Many strategies have been proposed in viticulture to manage global warming. Rootstocks are among them since they may affect water uptake and the scion’s performance.
The study conducted in La Rioja, Spain, aimed to investigate the impact of different rootstocks (1103P and 161-49C) on the performance of the Tempranillo grapevine scion over a three-day cycles under drought and extreme conditions, specifically during a heatwave in July 2022, with maximum air temperatures up to 40ºC and average daily temperatures of 29.1ºC.

The concept of « terroir »: what does that mean ? What is it useful for ? French young adults perception

Far from complicated discussions on the relevant way to define « terroir », this article deals with the social perception that French young adults (aged from 18 to 30) have of this concept and the way it can help them to become wine consumers.

PHENOTYPIC DIVERSITY AND BIO-PROTECTION CAPABILITY OF METSCHNIKOWIA SP. IN OENOLOGY

Nowadays, the trend is to reduce the use of chemical inputs in the food sector, including in oenology. One of the inputs widely used in the wine making process are sulfites, for its several properties: antimicrobial and antioxidiant. This use isn’t without consequences on consumer’s health and environment, it can lead for example to allergic reactions and pollution. To limit the addition of chemical inputs, microbial alternatives are used. It consists to inoculate in grape must, a micro-organism able to inhibit the growth of the negative indigenous flora during the phase before the fermentation and to guarantee the sensory qualities of wines.