1. Canadian Grain Commission, Grain Research Laboratory, 1404-303 Main Street, Winnipeg, Manitoba, Canada R3C 3G8. Contribution No. 755.
2. Corresponding author: 204/983-6054; Fax 204/983-0724, E-Mail: jdexter@cgc.ca.
3. Agriculture and Agri-Food Canada, Semiarid Prairie Agricultural Research Centre, Box 1030, Swift Current, Saskatchewan, Canada S9H 3X2.