1. Directorate Plant Sciences, Western Cape Department of Agriculture, Elsenburg, South Africa
2. Department of Horticultural Science, Stellenbosch University, South Africa
3. Agri Technovation, Head of Itest™ carbohydrates and Itest™ leaf, Wellington Industrial Area, South Africa
4. Department of Botany and Zoology, Stellenbosch University, South Africa
5. Research Scientist (Foliar Nutrition), Research and Development Division, Yara Farming Solutions, York, United Kingdom
6. School of Agriculture and Food Sciences, Faculty of Science, The University of Queensland, Australia