GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 Under trellis cover crop induces grapevine tolerance to bunch rot

Under trellis cover crop induces grapevine tolerance to bunch rot

Abstract

Context and purpose of the study – Botrytis bunch rot occurrence is one of the most important limitations for the wine industry in humid environments. A positive correlation between grapevine growth and susceptibility to fungal pathogens has been found. In theory the effect of grapevine vegetative growth on bunch rot expression results from direct effects (cluster architecture, nitrogen status among others) and indirect ones (via microclimate). However, a reduction in bunch rot incidence can be achieved in some circumstances without major vine growth reduction. The present study was aimed to test the general hypothesis that bunch rot susceptibility is affected by vine vigor, but other factors associated with grapevine vegetative expression could be even more relevant.

Material and methods – The experiment was conducted over three growing seasons in Southern Uruguay. We tested Vertical Shoot Positioned (VSP) versus Lyra trellis systems with conventional flour management consisting alleyway tall fescue with 1.0 m wide weed-free strips under the trellis (VSP-H and Lyra-H), and VSP with under-trellis cover crop (VSP-UTCC). UTCC consists in the full cover of the vineyard soil with tall fescue (Festuca arundinacea). In all treatments, deficit drip irrigation was provided at mid-day stem potential (SWP) thresholds of -0.9 MPa. Treatments were arranged in a split-plot randomized block design with trellis system (Lyra vs VSP) as main plots and flour management schemes (H vs UTCC) as subplots. Shoot growth rate, SWP, berry size, berry composition (titratable acidity, Brix, and yeast available nitrogen) and bunch rot incidence and severity were monitored over the seasons, as well as final vine yield, cluster weights, berryfirmness and pruning weights.

Results – In VSP-H and Lyra-H treatments Botrytis bunch rot incidence progressively increased with pruning weight per meter of cordon length (PW/m). However, even associated with an increased number of shoots per vine, Lyra significantly reduce vine vigor, average disease occurrence was comparable between both trellis systems. Contrarily, bunch rot incidence was every season remarkably lower in VSP-UTCC compared to Herbicide treatments (Lyra-H and VSP-H) even when vegetative development (shoot elongation rate, PW/m, PAR%) and fruit maturation (TSS, titratable acidity) was compared to Lyra-H. Associated with berry weight, bunch size was significantly reduced by VSP-UTCC treatment.These may underline the important role of cluster architecture in the lower B. cinerea infection. However, the strong difference observed in disease occurrence between UTCC and H treatment in our study could not be explained by just this factor since UTCC also significantly affected other bunch rot infection triggers (reduced juice N levels and increased berry firmness). Botrytis bunch rot is a complex disease, and many of the three-way interactions (host, environment and pathogen) are poorly understood. Our results don’t allow to identify the specific mechanism by which UTCC induced a higher tolerance to botrytis bunch rot, however a clear effect on pathogen or host plant behavior was detected. Its seems to be more related to direct factors than indirect ones associated with canopy microclimate.

DOI:

Publication date: September 20, 2023

Issue: GiESCO 2019

Type: Poster

Authors

Andrés CONIBERTI1*, Virginia FERRARI1, Edgardo DISEGNA1, Mario GARCIA PETILLO2, Alan N. LAKSO3

1 Programa Fruticultura, Instituto Nacional de Investigación Agropecuaria, Canelones Uruguay
2 Departamento de Suelos y Aguas, Facultad de Agronomia, UdelaR., Montevideo, Uruguay
3 Department of Horticulture, College of Agriculture and Life Science, Cornell University. Geneva, NY USA

Contact the author

Keywords

Tannat, Botrytis bunch rot, under trellis cover crop, Fescue, vine vigor

Tags

GiESCO | GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Climate ethnography and wine environmental futures

Globalisation and climate change have radically transformed world wine production upsetting the established order of wine ecologies. Ecological risks and the future of traditional agricultural systems are widely debated in anthropology, but very little is understood of the particular challenges posed by climate change to viticulture which is seen by many as the canary in the coalmine of global agriculture. Moreover, wine as a globalised embedded commodity provides a particularly telling example for the study of climate change having already attracted early scientific attention. Studies of climate change in viticulture have focused primarily on the production of systematic models of adaptation and vulnerability, while the human and cultural factors, which are key to adaptation and sustainable futures, are largely missing. Climate experts have been unanimous in recognising the urgent need for a better understanding of the complex dynamics that shape how climate change is experienced and responded to by human systems. Yet this call has not yet been addressed. Climate ethnography, coined by the anthropologist Susan Crate (2011), aims to bridge this growing disjuncture between climate science and everyday life through the exploration of the social meaning of climate change. It seeks to investigate the confrontation of its social salience in different locations and under different environmental guises (Goodman 2018: 340). By understanding how wine producers make sense of the world (and the environment) and act in it, it proposes to focus on the co-production of interdisciplinary knowledge by identifying and foreshadowing problems (Goodman 2018: 342; Goodman & Marshall 2018). It seeks to offer an original, transformative and contrasted perspective to climate change scenarios by investigating human agency -individual or collective- in all its social, political and cultural diversity. An anthropological approach founded on detailed ethnographies of wine production is ideally placed to address economic, social and cultural disruptions caused by the emergence of these new environmental challenges. Indeed, the community of experts in environmental change have recently called for research that will encompass the human dimension and for more broad-based, integrated through interdisciplinarity, useful knowledge (Castree & al 2014). My paper seeks to engage with climate ethnography and discuss what it brings to the study of wine environmental futures while exploring the limitations of the anthropological environmental approach.

Mapping and tracking canopy size with VitiCanopy

Understanding vineyard variability to target management strategies, apply inputs efficiently and deliver consistent grape quality to the winery is essential. However, despite inherent vineyard variability, the majority are managed as if they are uniform. VitiCanopy is a simple, grower-friendly tool for precision/digital viticulture that allows users to collect and interpret objective spatial information about vineyard performance. After four years of field and market research, an upgraded VitiCanopy has been created to achieve a more streamlined, technology-assisted vine monitoring tool that provides users with a set of superior new features, which could significantly improve the way users monitor their grapevines. These new features include:
• New user interface
• User authentication
• Batch analysis of multiple images
• Ease the learning curve through enhanced help features
• Reporting via the creation of colour maps that will allow users to assess the spatial differences in canopies within a vineyard.
Use-case examples are presented to demonstrate the quantification and mapping of vineyard variability through objective canopy measurements, ground-truthing of remotely sensed measurements, monitoring of crop conditions, implementation of disease and water management decisions as well as creating a history of each site to forecast quality. This intelligent tool allows users to manage grapevines and make informed management choices to achieve the desired production targets and remain profitable.

austrianvineyards.com: online viewer of all designations of Austrian wine

To digitally record and present all the origins of Austrian wines in the same perfect and clear way was the motivation for the Austrian Wine Marketing Board (Austrian Wine) to start with the project in 2018. In June 2021 the results were presented to the public in an online viewer showing all the designations of Austrian wine, available at https://austrianvineyards.com in a largely barrier-free manner. The online viewer provides tailored individual maps fitted to the respective zoom level. The smallest unit of wine-origins in Austria is called Ried and is displayed in a plot-specific manner highlighting areas under vine. Information on the Ried include administrative district, winegrowing municipality, cadastral municipality, large collective vineyard site, specific winegrowing region, generic winegrowing region, winegrowing area and, in many cases, an illustrative picture. Complementary data on the size, elevation (minimum-maximum), orientation (in 8 sectors plus flat) and gradient (minimum, maximum, average) are based on the area under vine according to the EU’s Integrated Administration and Control System. Additional information covers climate data. The diagrams are taken from the monthly breakdown of data in the annals of the Central Institute for Meteorology and Geodynamics, Austria provide a display of values for air temperature, precipitation, and sunshine hours for the reference year and the long-term average. Seasonal aggregated data on temperature, precipitation, and sunshine hours complete the display. Short descriptions with emphasis on geology and soil, field name in historical maps, etymology of the denomination, and main planted variety complements the available information for the main designations in the online viewer. These descriptions are compiled by winegrowers, geologists, historians, and journalists. All the information and data can be extracted to a pdf-file. Printed vineyard maps are also available. Missing content regarding wine origins in Styria will be completed in winter 2021/22.

Water deficit differentially impacts the performances and the accumulation of grape metabolites of new varieties tolerant to fungi

The use of resistant varieties is a long-term but promising solution to reduce chemical input in viticulture. Several important breeding programs in Europe and abroad are now releasing a range of new hybrids performing well regarding fungi susceptibility and producing good quality wines. Unfortunately, insufficient attention is paid by the breeders to the adaptation of these varieties to climatic changes, notably to the increased climatic demand and water deficit (WD). Thus, prior to the adoption of such varieties by the wine industry in Mediterranean regions, there is a need to consider their suitability to WD. This study aimed to characterize the different drought-strategies adopted by 6 new resistant varieties selected by INRAE in comparison to Syrah. To allow the assessment of long-term impacts of WD, field-grown vines were exposed to contrasted WD from 2018 to 2021 under a semi-arid Mediterranean climate. A gradient of WD was applied in the field and controlled through plant measurements at the single plant level. Grape development was non-destructively monitored to determine the arrest of berry phloem unloading. The impacts of WD on berry composition, including water, primary metabolites (sugars, organic acids), secondary metabolites (anthocyanins, thiols precursors) and main cations contents, were assessed at this specific stage. Results showed different varietal responses during the year and inter-annual acclimation in terms of plant water use efficiency, biomass accumulation, as well as yield components and berry composition. WD differentially reduced the accumulation of primary metabolites at plant and berry levels, but it little changed their concentrations in the fruits at the ripe stage. Moreover, WD differentially impacted the accumulation of secondary metabolites and major cations between the varieties. In the talk, we’ll present the main results regarding the WD impacts on fruit metabolites and enlarge the reflection about the practical assessment of the grapevine acclimation to WD.

Mesoclimate impact on Tannat in the Atlantic terroir of Uruguay

The study of climate is relevant as an element conditioning the typicity of a product, its quality and sustainability over the years. The grapevine development and growth and the final grape and wine composition are closely related to temperature, while climate components vary at mesoscale according to topography and/or proximity to large bodies of water. The objective of this work is to assess the mesoclimate of the Atlantic region of Uruguay and to determine the effect of topography and the ocean on temperature and consequently on Tannat grapevine behavior.