1. Department of Genetics, Stellenbosch University, Stellenbosch, South Africa
2. Citrus Research International (Pty) Ltd, Nelspruit, South Africa
3. Avima (Pty) Ltd, P.O. Box 45, Nelspruit, South Africa
4. Directorate Inspection Services, Department of Agriculture, Land Reform and Rural Development, Pretoria, South Africa
5. Department of Plant Pathology, Stellenbosch University, Stellenbosch, South Africa