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…

First step in the preparation of a soil map of the Protected Designation of Origin Valdepeñas (Central, Spain)

This work is a first step to make a map of vineyard soils. The characterization of the soils of the Protected Designation of Origin (D.P.O.) Valdepeñas will allow to group the studied profiles according to their physico-chemical characteristics and the concentrations of most relevant chemical elements. 90 soil profiles were analysed throughout the territory and the soils were sampled and described according to FAO (2006) and classified according to and Soil Taxonomy (2014). All samples were air dried, sieved and some physico-chemical parameters were determined following standard protocols. Also, major and trace elements were analysed by X-ray fluorescence. The statistically study was made using the SPSS program. Trend maps were made using the ArcGIS program. The studied soils have the following average properties: pH, 8.3; electrical conductivity, 0,20 dS/m (low); clay, 18.8% (medium) and CaCO3, 17.1% (high). In the study for the major elements. The major elements of these soils are Si, followed by Ca and Al, with an average content of 203.7 g/kg, 105.5 g/kg and 74.0 g/kg respectively. On the other hand, 27 trace elements have been studied. Of all of them, it can be highlighted the average values of Ba (361.8 mg/kg), Sr (129.3 mg/kg), Rb (83.4 mg/kg), V (74.2 mg/kg) and Ce (70.6 mg/kg). Ba, V and Ce values are higher and the values of Sr and Rb are lower to those found in the literature. The discriminant analysis shows a percentage of grouping of 91%. The content of chemical elements together with the physico-chemical characteristics allows grouping the soils in 4 group according to their order in the classification to Soil Taxonomy; due to the importance of the Calcisols in Castilla-La Mancha, it has been decided to establish them as their own group even if they do not appear in Soil Taxonomy classification.

Effect of one-year cover crop and arbuscular mycorrhiza inocululation in the microbial soil community of a vineyard

The microbial composition of the soil is an important factor to consider in viticulture, since its influence on the “terroir” and on the organoleptic properties of the wine have been demonstrated. Different agronomic techniques have the potential to modify the composition and functionality of the soil microbial community. Maintaining green covers is known to increase soil microbial diversity. The direct application of inoculum of beneficial microorganisms to the soil has also been used to increase their abundance. However, the environmental conditions of each site seem to have a determining weight in the result of these practices. In this study, we compared the effect on the microbial community of a cover crop with legumes in autumn and the inoculation of grapevines with commercial inoculum bases on Rhizophagus irregularis and Funeliformis mosseae in the previous spring. The study has been carried out in a vineyard in Binissalem, Mallorca, Spain. After applying the treatments, we will analyze the soil microbial communities using the data obtained from Illumina amplification of soil DNA from the 16S and ITS regions to analyze bacteria and fungi community, respectively. In addition, we will record the physicochemical characteristics of the soil at each sampling point. The result showed that agronomic management, in the short term, has less influence than soil characteristics on the composition of the soil microbiome. With these results, we can conclude that in a vineyard, agricultural techniques should focus on improving the characteristics of the soil to improve the biodiversity of the soil microbiota.

Climate projections over France wine-growing region and its potential impact on phenology

Climate change represents a major challenge for the French wine industry. Climatic conditions in French vineyards have already changed and will continue to evolve. One of the notable effects on grapevine is the advancing growing season. The aim of this study is to characterise the evolution of agroclimatic indicators (Huglin index, number of hot days, mean temperature, cumulative rainfall and number of rainy days during the growing season) at French wine-growing regions scale between 1980 and 2019 using gridded data (8 km resolution, SAFRAN) and for the middle of the 21th century (2046-2065) with 21 GCMs statistically debiased and downscaled at 8 km. A set of three phenological models were used to simulate the budburst (BRIN, Smoothed-Utah), flowering, veraison and theoretical maturity (GFV and GSR) stages for two grape varieties (Chardonnay and Cabernet-Sauvignon) over the whole period studied. All the French wine-growing regions show an increase in both temperatures during the growing season and Huglin index. This increase is accompanied by an advance in the simulated flowering (+3 to +9 days), veraison (+6 to +13 days) and theoretical maturity (+6 to +16 days) stages, which are more noticeable in the north-eastern part of France. The climate projections unanimously show, for all the GCMs considered, a clear increase in the Huglin index (+662 to 771 °C.days compared to the 1980-1999 period) and in the number of hot days (+5.6 to 22.6 days) in all the wine regions studied. Regarding rainfall, the expected evolution remains very uncertain due to the heterogeneity of the climates simulated by the 21 models. Only 4 regions out of 21 have a significant decrease in the number of rainy days during the growing season. The two budburst models show a strong divergence in the evolution of this stage with an average difference of 18 days between the two models on all grapevine regions. The theoretical maturity is the most impacted stage with a potential advance between 40 and 23 days according to wine-growing regions.

Short-term relationships between climate and grapevine trunk diseases in southern French vineyards

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Modulation of berry composition by different vineyard management practices

High concentration of sugars in grapes and alcohol in wines is one of the consequences of climate change on viticulture production in several wine-growing regions. In order to investigate the possibilities of adaptation of vineyard management practices aimed to reduce the accumulation of sugar during the maturation phase without reducing the accumulation of anthocyanins in grapes, a study with severe shoot trimming, shoot thinning, cluster thinning and date of harvest was conducted on Merlot variety in Istria region (Croatia), under the Mediterranean climate. Four factors which may affect grape maturation and its composition at harvest were investigated in a two-years experiment; severe shoot trimming applied at veraison when >80% of berries changed colour (in comparison to untreated control), shoot thinning (0 and 30%), cluster thinning (0 and 30%), and the date of harvest (early and standard harvest dates). Shoot thinning had no significant impact on berry composition, despite the obtained reduction in yield per vine. Lower Brix in grapes were obtained with earlier harvest date and if no cluster thinning was applied, although at the same time a reduction in the concentration of anthocyanins in berries was observed in these treatments. On the other hand, if severe shoot trimming was applied when >80% of berries changed colour, a reduction of Brix was obtained without a negative impact on berry anthocyanins concentration. We conclude that in cases when undesirably high sugar concentrations at harvest are expected, severe shoot trimming at 80% veraison may effectively be used in order to obtain moderate sugar concentration in berries together with the adequate phenolic composition.