Prior to moving to Australia to do a PhD in Viticulture, Zelmari was a technical assistant at the Stellenbosch University in South Africa for nine years and during this period completed her MScAgric (cum laude) part-time. Zelmari has worked with industry on two projects during this time, first by managing a terroir project on commercial vineyards in and around Stellenbosch, which focused on the response of Sauvignon Blanc and Cabernet Sauvignon to the environment, and thereafter on the establishment of the berry sugar loading harvest tool at certain commercial wineries in South Africa. A part of the terroir project was written up as her MScAgric thesis. Before leaving South Africa, she mainly managed an integrated project which focused on the influence of light and temperature at the vine and bunch level on growth and ripening of Sauvignon Blanc berries. In addition to viticulture research, she also worked on climatology with an international team and geographical information systems during the studies.
In 2014, Zelmari was awarded an ARC Training Centre for Innovative Wine Production scholarship. The training centre is administered under the University of Adelaide with Charles Sturt University (National Wine and Grape Industry Centre), CSIRO and DPI-NSW as partners on this project.
Focus area: The sugar-potassium nexus within the grape berry.
This project is one of 12 projects under the ARC Training Centre for Innovative Wine Production with an overall aim towards the production of lower alcohol wines. This project is focusing on manipulation of the sugar content in the grape berries prior to harvest, thus from a viticultural angle.
It is speculated that there is a relationship between the loading of sugar and potassium into the grape berry during ripening due to similar accumulation patters noticed in previous studies. If this link exist, and the possible drivers of this link, has however not been determined as of yet.
The aim of the PhD project is to define this possible link between the sugar and potassium accumulation within the grape berry, and if there is an applicable way to decrease sugar accumulation through the manipulation of potassium.
Šuklje K., Lisjak K., Baša Česnik H., Janeš L., Du Toit W.J.,Coetzee ZZ., Vanzo A. and Deloire A. 2012. Classification of grape berries according to diameter and total soluble solids to study the effect of light and temperature on methoxypyrazines, glutathione and hydroxycinnamates evolution during ripening of Sauvignon Blanc (Vitis vinifera L.). Journal of Agricultural and Food Chemistry, 60, 9454-9461.
Šuklje, K., Antalick, G., Coetzee, Z., Schmidtke, L., Baša Česnik, H., Brand, J., Du Toit, W., Lisjak, K. and Deloire, A. 2014. Effects of leaf removal and ultraviolet radiation in the vineyard on the composition and sensory perception of Sauvignon Blanc (Vitis vinifera L.) wine. Australian Journal of Grape and Wine research, 20(2), 223-233.
Šuklje, K., Antalick, G., Buica, A., Langlois, J., Coetzee, Z.A., Gouot, J., Schmidtke, L.M. and Deloire, A. 2015. Clonal differences and impact of defoliation on Sauvignon blanc (Vitis vinifera L.) wines: a chemical and sensory investigation. Journal of the Science of Food and Agriculture, DOI: 10.1002/jsfa.7165.
Bonnardot, V., Carey, V., Cautenet S., Madelin, M., Coetzee, Z. and Quénol, H., 2014. Changement climatique et variabilité spatiale des températures à fine échelle dans les vignobles de Stellenbosch (Afrique du Sud) In: Changement climatique et terroirs viticoles, Edition: Tech&Doc, Editors: Lavoisier, pp.247-266.
Bonnardot, V., Carey, V., Madelin, M., Cautenet, S., Coetzee, Z. and Quenol, H. 2012. Spatial variablility of night temperatures at a fine scale over the Stellenbosch wine district, South Africa. Journal International des Sciences de la Vigne et du VIn, 46, 1-13.