Project Number
WW 13-10
Project title
Aptitude of the cultivar Chenin blanc for botrytisation: Application to viticultural zoning to obtain dry and sweet wines
Project leader
Carey, V A
Project description
Preliminary studies in France have shown that the development of the Botrytis cinerea and its evolution towards grey or noble rot is closely related to the terrain (via its effect on the performance of the vine). This hypothesis is being tested in both South Africa and France in order to assist in the identification of terrains suitable for the production of dry or sweet white wines.
The vegetative growth and chemical composition of the berries were monitored during the growth season at five experimental plots of Chenin blanc vines on Richter 99 (or Ramsay in the case of Slent). Vines are of a similar age in existing vineyards in close proximity to weather stations in the Paarl area. In the second half of the growth season the development of Botrytis cinerea infections and natural desiccation of the grape berries were followed. Small scale dry wines were made from the 24 reference vines and natural sweet wines were made at appropriate stages.
Unfortunately the 2000 – 2001 vintage was not conducive to infection by Botrytis cinerea and a producer harvested one of the five experimental plots, resulting in loss of data. It can, however, be noted that different sites result in different growth and maturation patterns of the same vegetative material. Experimental wines were made at maturity and at super maturity from selected grapes in order to show the effect of site on wine style and quality. It is recommended that a plot at Villiera replace the experimental plot at Slent, because the grapes at this plot have been harvested during both seasons and because it is necessary to include a plot in a cooler region.
Poster(s)
Carey, V A, Barbeau, G, Bonnardot, V M F and Vermeulen, A K. 2000. Heat injury to bunches of Vitis vinifera cv. Chenin blanc: A comparison between the Mid-Loire Valley, France and Paarl, South Africa. Poster presented at the 2nd International Congress of the South African Society for Enology and Viticulture. 8-10 November, Somerset West, South Africa.
Carey, V A, Barbeau, G, Conradie, W J and Vermeulen, A K. 2000. Monitoring the development of Botrytis cinerea on Vitis vinifera L.cv. Chenin blanc: description of a comprehensive methodology. Poster presented at the 2nd International Congress of the South African Society for Enology and Viticulture, 8-10 November, Somerset West, South Africa.
Presentation(s)
Carey, V A, Barbeau, G, Cadot, Y, Conradie, W J and Vermeulen, A K. 2004. The implications of terroir for development of Botrytis cinerea into grey rot or noble on grapes of Vitis vinifera L.cv. Chenin blanc. Paper presented at 24th World Congress of the Vine and Wine and the 79th General Assembly of the OIV. 4-9 July 2004, Vienna, Austria.