1. National Research Council, Plant Biotechnology Institute, 110 Gymnasium Place, Saskatoon, SK, S7N OW9, Canada.
2. University of Saskatchewan, Crop Development Centre, 51 Campus Drive, Saskatoon, SK, S7N 5B1, Canada.
3. Tohoku National Agricultural Experiment Station, Akahira 4, Morioka, Iwate 020-01, Japan.
4. Corresponding author. Fax: 306/975-4839. E-mail: rchibbar@pbi.nrc.ca