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…

Ripening of cv. Cabernet Sauvignon grapes: polysaccharides fractions evolution and phenolic extractability

Polysaccharides and more specifically pectins, make up a significant portion of the cell wall material of the plant cells including the grapes. During the fruit ripening the associated softening is related to the breakdown of the cell wall polysaccharides. During this process, it is expected that polysaccharides that are soluble in red wine will be formed influencing its texture. Anthocyanins are responsible for the wine color and tannins for the astringency, body and bitterness of the wine. In the skins, these compounds are located in the cell vacuoles and the barrier that conditions their extractability is the skin cell wall that may determine the mechanical resistance, the texture and the ease of processing berries. The aim of this work was study the evolution of the polysaccharides and the anthocyanin and tannin extractability during the ripening period in Cabernet Sauvignon grapes, trying to correlate these variables.

Antimicrobial activity of oenological polyphenols against Gram positive and Gram negative intestinal multidrug-resistant bacteria

Bacterial antibiotic resistance is a major current health problem. Polyphenols have demonstrated antibacterial activity, and in this work we studied the effect of oenological polyphenols on the growth of intestinal multidrug-resistant strains of human and animal origin. Two Enterococcus faecium strains, resistant to vancomycin and other antibiotics, and four Escherichia coli strains, resistant to ampicillin and other antibiotics, were included in this study. All strains showed multidrug resistant phenotypes and genotypes to at least two antibiotic families.

From average to individual fruit, a paradigm shift for accurate analysis of water accumulation and primary metabolism in developing berries

Presentknowledge about grape development is mainly driven by the premise that a typical berry would follow the same kinetics as the population average

TCA – A status report on South African cork closures

Cork taint decreases the commercial value of wine as tainted wines are rejected by consumers. Although other compounds in wine and cork can also be responsible for causing a taint, 2,4,6-trichloroanisole (TCA) is regarded as the primary cause of cork taint. As cork taint is often used in marketing campaigns against natural cork closures,

Analysing consumers’ decision-making process for non-alcoholic spirit drinks and dehalcolized aromatized wines 

In recent years, the consumption of alcoholic beverages is changing, driven by evolving consumer preferences and societal trends, including a wave of health consciousness. Among these changes, the emergence and proliferation of nolo (no alcohol/low alcohol) alcoholic beverages have gained significant attention within the industry. Nolo alcohol beverages are produced to emulate the appearance, aroma, and taste of alcoholic beverages, potentially facilitating a sense of social integration when consuming a product that closely resembles alcohol.