Terroir 2020 banner
IVES 9 IVES Conference Series 9 Regulated deficit irrigation and crop load interaction effects on grape heterogeneity

Regulated deficit irrigation and crop load interaction effects on grape heterogeneity

Abstract

Aim: To investigate the interaction effects between irrigation and crop load and the resulting impact on grape heterogeneity within a Geographical Indication in South Australia. 

Methods and Results: Cabernet Sauvignon grapes were sampled at the time of harvest from the Coonawarra Geographical Indication where full and sustained deficit irrigation and crop load manipulations were implemented as a 2 × 2 factorial block design. Grape heterogeneity was quantified for each treatment at three levels (bunch, vine and block) using berry density categories that were related to grape maturity. Furthermore, each density category was characterised in terms of total soluble solids, berry fresh weight, tannin content and tartaric and malic acid concentrations. Irrigation and crop load interaction effects on grape heterogeneity were observed for intra- cluster, vine, and between blocks.

Conclusion: 

This research reveals the extent of heterogeneity existing in the vineyard at the time of harvest, and presents management techniques that may mitigate grape ripeness variation in the vineyard.

Significance and Impact of the Study: Grape heterogeneity is an important consideration for the production of high quality red wine, as high proportions of under ripe and/or overripe fruit present at the time of harvest have been shown to negatively impact colour, mouthfeel, and varietal aroma of the wine. Furthermore, the presence of overripe/shrivelled grapes with excessive sugar concentrations can lead to increased ethanol in the wine. Previous research has acknowledged the impact that the three focal aspects of terroir – climate, soil and cultivar – have on grape composition, with the overarching effects of climate being highlighted. Vine water status and vine balance can conceivably mediate some of the influences of climate on grape composition, but there has been limited literature delving into the effects on grape heterogeneity. By investigating vineyard management techniques with a view to minimising grape heterogeneity, this research gives insight into the optimisation of grape production, especially in hotter climates that are more susceptible to producing overripe fruit.

Download the PDF

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type: Video

Authors

Claire Armstrong1,2, Pietro Previtali1,2, Vinay Pagay1,2, Paul Boss1,3, David Jeffery1,2*

1 ARC Training Centre for Innovative Wine Production, The University of Adelaide, PMB 1 Glen Osmond, SA, 5064, Australia
2 The Waite Research Institute and The School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond, SA, 5064, Australia
3 CSIRO Agriculture and Food, Locked Bag 2, Glen Osmond, SA 5064, Australia

Contact the author

Keywords

Vineyard management techniques, vineyard variation, grape composition, Cabernet Sauvignon, red wine quality

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Water retention properties of viticultural calcisols from D. O. P. Valdepeñas (Spain)

A good knowledge of the soil physicochemical properties, as well as its ability to retain and put the necessary water available to the plants, is essential when it comes at the design of an irrigation plan.

Read More

Genomic characterization of terpene biosynthetic genes in seven Vitis vinifera L. varieties 

Grapes (Vitis vinifera L.) are a fruit crop of high economic significance globally. Each grapevine cultivar is characterized by its distinctive grape aroma, affecting the wine quality. In several cultivars, the aroma is shaped by terpenoid (mono- and sesqui-terpenoids). Their profile is controlled by terpene synthases (TPS), which are part of a largely expanded gene family. How the variation in TPS copy number and sequence among cultivars determines terpenoid profiles of grapes remains largely unexplored. We annotated TPS in the haplotypes of seven genomes (Riesling, Albariño, Fiano, Gewürztraminer, Pinot Noir, Cabernet Sauvignon, and Viognier) using BLAST, GMAP, PFAM, and phylogenetic analyses. Further, TPS expression patterns and terpenoid accumulation during berry development and ripening were characterized using RNA-Seq and SPME/GC-MS platforms, respectively. Variation in TPS copy number exists among cultivars. Specifically, the TPS counts span a range of 251 to 150 for Riesling and Fiano, respectively, when considering combined haplotypes within each cultivar. Total terpenoid accumulation patterns throughout development were consistent among the five aromatic cultivars, marked by high concentrations in flowers, followed by a decline and subsequent rise during berry development and ripening, respectively. Conversely, non-aromatic cultivars exhibited no substantial increase in terpenoid concentration during ripening. Transcriptome and network analyses are currently employed to determine which TPS are expressed in the berry and determine the terpenoid profile of the specific cultivar. These findings shed light on the genomic determinants of grape aroma in major cultivars, and allow future studies focused on cultivar-specific responses of terpenoid biosynthesis to environmental stresses.

Read More

Représentation holistique d’une dynamique pluridisciplinaire suite à la cartographie des sols en Beaujolais

Une démarche de cartographie des sols a été engagée en 2009 par l’interprofession des vins du Beaujolais à l’initiative des professionnels de la région. A fin 2015

Read More

Investigating the carbon sequestration potential in vineyard soils–the SUSTAIN project

The SUSTAIN project aims at assessing the soil organic carbon (SOC) stock and vulnerability in vineyard in a climate change scenario.

Read More

Optimization of aroma production in grape cell suspensions induced by chemical elicitor

Methyl-jasmonate (MeJA) induces the production of at least 25 compounds with sesquiterpene- like mass spectra in ‘Cabernet sauvignon’. Tost effective concentration of MeJA in stimulating the production of sesquiterpenes was found to be 500 µM if added when the cell suspensions had a PCV of 35 %, and 1000 if added when the cell suspensions had a PCV of 70 %.

Read More