1. Department of Molecular Biology and Genetics, University of Guelph, Guelph, Ontario N1G 2W1, Canada
2. Pioneer Hi-Bred Production Limited, Canola Research Station, 12111 Mississauga Road, Georgetown, Ontario L7G 4S7, Canada
3. Biology Department, York University, 4700 Keele Avenue, North York, Ontario M3J 1P3, Canada