IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Viticultural and enological strategies for the prevention of Botrytis cinerea- induced quality losses

Viticultural and enological strategies for the prevention of Botrytis cinerea- induced quality losses

Abstract

Infection of the grapes with Botrytis cinerea has a tremendous impact on the resulting crop yield and quality. Well-known problems that are associated with B. cinerea are specific off-flavors, poor filterability, and brownish color in white wines. The development of a B. cinerea infection strongly depends on weather conditions and is highly variable through different vintages. Typical control measures include defoliation and the use of fungicides, which involves high personnel and material costs. They also involve a great risk, especially since the effectiveness and time point of these treatments are difficult to predict. The frequency and severity of B. cinerea infections in Germany will increase due to climate change-induced alteration of weather conditions and the rise of new pathogen strains. In warmer, drier years, heavy Botrytis infection has already been observed, indicating the development of more aggressive strains. Common practices to deal with the negative effects of Botrytis on wine quality have been demonstrated to be ineffective and need to be reconsidered. To approach this problem, first experiments investigating oenological usage of coal and tannins in Botrytis infested must have been conducted. Sensory analysis and CATA confirmed, that common practices are not sufficient enough to battle Botrytis induced off-flavors. According to our results no clear positive effect of tannin treatment could be observed. To obtain more insight into the diversity of Botrytis strains, a PCR fingerprinting method is going to be established, as well as a qPCR method for biomass detection in to obtain more knowledge about climate based developments of B. cinerea. A method for detecting Botrytis induced aroma compounds like Geosmine and 1- Octen- 3-ol, was optimized by using a new CG-MS method. First results show success in validating different strains as well as detecting different aroma compounds in GC-MS.

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Backmann Louis1, Umberath Kim-Marie2, Wegmann-Herr Pascal1 and Scharfenberg-Schmeer Maren3

1Institute for Viticulture and Enology (DLR-Rheinpfalz)
2Institute of Nutritional and Food Sciences, Bonn
3Microbiology, HS Kaiserslautern 

Contact the author

Keywords

Botrytis,enological treatments, sensory analysis,PCR, qPCR, GC-MS

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Relationship between soil and grapevine variety in the wineyard of Jura: example for the “Trousseau” variety from the “Terroir” of Montigny-Lès-Arsures (France)

Seven plots located in the commune of Montigny-lès-Arsures (Jura, 39), planted with grapevine varieties Trousseau and Savagnin, were chosen for a study of soil pits and a distribution of major and trace chemical elements in soils and wines. It was shown that the mineral matrix of the soil reflects the geological substratum and the sub-surface alteration process, while the organic soil matrix depends on agro-viticultural practices.

Identification of aroma markers in amarone wines

Amarone is an Italian red wine produced in the Valpolicella area, in north-eastern Italy. Due to its elaboration with withered grapes, Amarone is a rather unique example of dry red wine. However, there is very limited data so far concerning the volatile composition of commercial Amarone wines, which also undergo a cask aging of 2-4 years before release. The present work aims at characterizing the aroma composition of Amarone and to elucidate the relationships between chemical composition and sensory characters. The analysis of 17 Amarone commercial wines from the same vintage (2015) was carried out by means of Gas Chromatography-Mass Spectrometry (GC-MS) and extracted by Solid Phase Extraction (SPE) and Solid Phase Micro Extraction (SPME). In addition, the sampled wines were subjected to a sensory evaluation in the form of sorting task.RESULTS: 70 volatile compounds were successfully identified and quantified, 30 of which were present in concentrations above their odor thresholds in all the samples. Using the odor activity value (OAV), the compounds that potentially contribute to Amarone perceived aroma are b-damascenone, ethyl and isoamyl acetate, ethyl esters (hexanoate, octanoate, butanoate, 3-methybutanoate), 4-ethyl guaiacol, 3-methylbutanoic acid, dimethyl sulfide (DMS), eugenol, massoia lactone, 1,4-cineol, TDN, cis/trans-whisky lactone. In certain samples, high OAVs were also observed for 4-ethyl phenol and 1,8-cineole.Results from the sorting task sensory analysis showed three clusters formed.

Exploring the physico-chemical modification of grape seed extracts to improve their clarifying effect in red wine

During winemaking, some byproducts are obtained, such as grape pomace, which represent 13% of winery byproducts.

Influence of a spontaneous cover crop on the vineyard and soil erosion under Mediterranean climate

Sixty five % of the agricultural area of the Basque Country located in the DO Ca Rioja corresponds to vineyards. More than 40% of it has an average slope greater than 10%, which makes it sensitive to erosive processes. Furthermore, it is foreseeable that extreme weather events (storms, hail, extreme heat and cold, etc.) will be favored due to climate change. Cover cropping can mitigate this risk, and therefore the objective of this work is to evaluate the impact that a vegetable cover has on the agronomic behavior of the vineyard, the quality of the grape and soil erosion. For this, a trial has been carried out with a Graciano variety vineyard with a slope between 10% -20% during the years 2020 and 2021. Conventional tillage management in the area has been compared (4-6 passes per year of tillage machinery) versus spontaneous vegetation cover management in the vineyard. This implies not tilling and allowing the grass of the land to colonize the range between the lines of vines, controlling their height through 1-3 mowing passes per year, always trying to affect the surface of the land as little as possible. The vegetative growth, yield and quality of the grape and wine was measured. Furthermore, erosion has been measured using Gerlasch boxes. The yield was lower in the second year of the trial in the cover crop treatment, but erosion was significantly reduced.

Grapevine productivity modelling in the Portuguese Douro Region

In Portugal, and particularly in the Demarcated Region of Douro (DDR), wine production has a great tradition, producing the unique and worldwide famous Port wine as well as other remarkably good table wines. In this study the impact of projected climate change to wine production is analysed for the DDR. A statistical grapevine yield model (GYM) is developed using climate parameters as predictors.