Wednesday, November 15, 2006
257-7
Winter Rapeseed Advances in North Dakota.
Burton L. Johnson, North Dakota State Univ., 1301 12th Ave. N., Fargo, ND 58105, Bryan K. Hanson, North Dakota Ag. Expt. Stn. Langdon Research Ext. Center, 1750 10th St., Landgon, ND 58249, and Paula J. Petersen, North Dakota State University, 1301 12th Ave. N., Fargo, ND 58105.
Previous evaluations of winter rapeseed (Brassica napus L.) in North Dakota during the early to mid 1980s indicated inadequate winter-hardiness, however recently development cultivars show greater winter-hardiness. Twenty current winter rapeseed genotypes were evaluated in a RCBD with three replicates, at Prosper, North Dakota, during 2003/2004 for fall and spring stand establishment, winter survival, flowering, and yield. Genotype spring stands ranged from 9 to 56% among the winter genotypes. Onset of flowering averaged 21 d earlier and flowering duration 4 d longer for the winter genotypes compared to the spring seeded check cultivar. Eight winter genotypes yielded equal to the spring seeded check cultivar with six other winter genotypes yielding from 65 to 83% of the spring seeded check cultivar. These results indicate substantial improvement in winter hardiness in North Dakota compared to earlier evaluations. This demonstrates plant breeding progress and need for continuance and also research to define cultural and other management factors that will facilitate success of winter rapeseed production.