Terroir 2004 banner
IVES 9 IVES Conference Series 9 Partial rootzone drying (PRD): strategic irrigation management as viticultural tool affecting plant physiology and berry quality

Partial rootzone drying (PRD): strategic irrigation management as viticultural tool affecting plant physiology and berry quality

Abstract

Partial rootzone drying (PRD) is an irrigation management technique designed to reduce water use in grapevines without a decline in yield, thereby increasing water use efficiency (WUE). The principle of PRD is to keep part of the root system at a constant drying rate to produce soil derived signals to above-ground plant organs to induce a physiological response resulting in viticultural effects. Major PRD effects include a reduced canopy size and greatly increased WUE with possible improvements in fruit quality. Experiments conducted under Australian conditions consisted of field-grown grapevines irrigated at variable rates to elucidate a true PRD effect. The effects of PRD on the assimilation and partitioning of C and N in grapevines are reported and the sustainability and economic potential of the PRD system are discussed. Major findings include the effects of PRD on grapevine physiology on the biochemical level where the source:sink relationship between plant organs influences dry matter accumulation and nitrogen assimilation that will influence fertilization needs. Finally, the effects of PRD on berry growth and quality are discussed, especially the accumulation of hexose, amino acids and inorganic ions such as K+, that may have an influence on wine quality.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

Gerhard du Toit

Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Victoria Street, ZA 7600 Stellenbosch, South Africa

Contact the author

Tags

IVES Conference Series | Terroir 2004

Citation

Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.