terclim by ICS banner
IVES 9 IVES Conference Series 9 Physiological means to curb the enthusiasm of viruses from infecting grapevines  

Physiological means to curb the enthusiasm of viruses from infecting grapevines  

Abstract

The two most deadly viruses infecting and threatening the productivity of grapevines worldwide are leafroll and red blotch viruses. There is no cure for viral diseases other than roguing the symptomatic vines and replacing them with certified vines derived from clean, virus-tested stocks. 
Given that phloem plays a central role in virus infection, this study aimed to purge the virus by girdling the phloem of leafroll-infected vines at different phenological stages of infected grapevines. Phloem-girdling was performed on canes at veraison to varying regions between the proximal and distal clusters. The vines responded to gridling by forming a callus to bridge the gap and restore vascular functionality. The whole lamina of the leaves above the girdled region turned red due to anthocyanin accumulation triggered by sugars confined to the leaf. This reddening was quite different from the reddening that typically occurs in the leafroll-infected vines, wherein the whole lamina turned red except for the lamina close to the major and minor veins, giving the impression of green veins. The girdled canes showed a low virus concentration compared to the ungirdled canes. Also, the primary metabolites, such as sugars, acids, and nitrogenous compounds, and the secondary metabolites, such as flavanols (tannins), flavonols, and anthocyanins desired for making wine did not vary much between the girdled and ungirdled shoots. This study showed that by girdling the phloem over several growing seasons can reduce the virus load in the infected vines, restoring the vine’s health.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Bhaskar Bondada*

Washington State University Tri-Cities, Wine Science Center, Richland, WA, USA

Contact the author*

Keywords

Acids, Anthocyanins, callus, girdling, phenolics, phloem, sugars

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

VOLATILE COMPOSITION OF WINES USING A GC/TOFMS: HS-SPME VS MICRO LLE AS SAMPLE PREPARATION METHODOLOGY

Wine aroma analysis can be done by sensorial or instrumental analysis, the latter involving several me-thodologies based on olfactometric detection, electronic noses or gas chromatography. Gas Chromatography has been widely used for the study of the volatile composition of wines and depending on the detection system coupled to the chromatographic system, quantification and identification of individual compounds can be achieved.

Application of fluorescence spectroscopy with multivariate analysis for authentication of Shiraz wines from different regions

Aim: To investigate the possibility of utilising simultaneous measurements of absorbance-transmittance and fluorescence excitation-emission matrix (A-TEEM) combined with chemometrics, as a robust method that gives rapid results for classification of wines from different regions of South Australia according to their Geographical Indication (GI), and to gain insight into the effect of terroir on inter regional variation.

Organic Oregon: an emerging experience in terroir tourism

Emerging from anthropology, climatology, ecology, gastronomy, geography and wine tourism, terroir tourism has been recently recognized to have potential for developing rural agriculture tourism

Impact of varying ethanol and carbonation levels on the odor threshold of 1,1,6-trimethyl-1,2-dihydronaphtalene (petrol off-flavor) and role of berry size and Riesling clones

1,1,6-trimethyl-1,2-dihydronaphtelene (TDN) evokes the odor of “petrol” in wine, especially in the variety Riesling. Increasing UV-radiation due to climate change intensifies formation of carotenoids in the berry skins and an increase of TDN-precursors1. Exploring new viticultural and oenological strategies to limit TDN formation in the future requires precise knowledge of TDN thresholds in different matrices. Thresholds reported in the literature vary substantially between 2 µg/L up to 20 µg/L2,3,4 due to the use of different methods. As Riesling grapes are used for very different wine styles such as dry, sweet or sparkling wines, it is essential to study the impact of varying ethanol and carbonation levels.

Managing precision irrigation in vineyards: hydraulic and molecular signaling in eight grapevine varieties

Understanding the physiological and molecular bases of grapevine responses to mild to moderate water deficits is fundamental to optimize vineyard irrigation management and identify the most suitable varieties. In Mediterranean regions, the higher frequency of heat waves and droughts highlights the importance of precision irrigation to meet vine water demands and demonstrates the necessity for a deeper understanding of the different physiological responses among varieties under water stress. In this context, previous reports show an interplay between stomatal regulation of transpiration and changes in leaf hydraulic conductivity, also with the involvement of aquaporins (AQPs), particularly under water stress. However, how those signaling mechanisms are regulated in different grapevine varieties along phenological phases is unclear.