Vine carbohydrate dynamics and source-sink relationships

Abstract

This report is based on a workshop convened to clarify what is known about vine carbohydrate dynamics and source-sink relationships and to identify gaps in knowledge. Among the 38 people attending were scientists and practitioners from across Australia, as well as two invited participants from the United States (Professor Alan Lasko of Cornell University and Professor David Eissenstat of Pennsylvania State University).

Summary

Workshop participants were presented with updates on research projects relating to the subjects, key influences on source-sink relationships and carbohydrate reserves were debated and groups were formed to identify research priorities.

Among topics discussed were the within-season dynamics, relationships between reserves of carbohydrates and grape yield and wine quality, the effects of long term deficit irrigation, implications of heat waves, drivers of healthy root development, and links between carbohydrate reserves and nitrogen.

Participants agreed not enough was known about carbohydrate dynamics and the related influences on grape production of water availability and nutrient status. It was recommended that research include measurements ranging from levels of reserves to quality parameters ascertained from small batch winemaking. This research, they argued, would build information about vine physiology, including the influence of environment, irrigation practices and carbohydrate availability on bunch primordial initiation, flower formation, flowering and fruit set.

The workshop summary is a valuable overview of the issues surrounding carbohydrates and source-sink relationships and contains useful references for scientists and grape growers with an interest in the topic.