1. European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (present address), formerly CSIRO Plant Industry, Black Mountain Laboratories, Canberra ACT 2601, Australia.
2. Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Brunszvik u. 2., Martonvásár 2462, Hungary.
3. NSW Department of Primary Industries, Tamworth Agricultural Institute, 4 Marsden Park Road, Calala, NSW 2340, Australia.
4. Department of Plant Physiology and Molecular Plant Biology, Eötvös Loránd University, Pázmány P 1/C, Budapest 1117, Hungary.
5. CSIRO Mathematical and Information Sciences, North Road, ANU Campus, Acton ACT, P.O. Box 664, Canberra, ACT 2601, Australia.
6. Corresponding author. Phone: +61 2 6216 7260. Fax: +61 2 6216 7111. E-mail: Bob.Anderssen@csiro.au