Published in Crop Sci. 46: 1963-1971 (2006)
© Crop Science Society of America
677 S. Segoe Rd. , Madison , WI 53711 USA

Organic Farming

Wheat Cultivar Performance on Certified Organic Fields
In Minnesota and North Dakota

Patrick M. Carr,* Herman J. Kandel, Paul M. Porter, Richard D. Horsley, and Steve F. Zwinger

P.M. Carr, North Dakota State Univ., Dickinson Res. Ext. Ctr., 1133 State Ave., Dickinson, ND 58601-3267; H.J. Kandel, Univ. Minnesota, Crookston Res. Ext. Ctr., 251 Owen Hall, 2900 Univ. Ave., Crookston, MN 56715-5001; P.M. Porter, Univ. Minnesota, Dep. Agron. Plant Gen., 411 Borlaug Hall, St. Paul , MN 55108-6026 ; R.D.

Horsley, North Dakota State Univ., Dep. Plant Sci., P.O. Box 5051, Fargo, ND 58105-5051; and S.F. Zwinger, North Dakota State Univ., Carrington Res. Ext. Ctr., P.O. Box 219 , Carrington , ND 58421 .

Synthetic agrichemicals are used to minimize nutrient deficiencies and pests when developing and selecting modern small-grain cultivars. Some farmers believe that modern cultivars are not adapted to environments without these inputs, and old cultivars should be grown. Our objective was to determine the adaptability of spring wheat ( Triticum aestivum L.) cultivars for production in certified organic environments.

A single seed lot for 15 cultivars and two seed lots each for two others were used to establish 19 treatments evaluated for grain yield, protein content, kernel and volume weight, along with phenotypical growth traits on four certified organic fields in Minnesota and North Dakota in 2003 and 2004. The cultivars represented different development eras, but 11 were released since 1995. Interactions between environments and cultivars existed for the four grain parameters (P , 0.05), but some modern cultivars ranked high consistently for yield, protein content, and volumeweight. For example, themodern cultivarWalworth produced an average of 500 kg ha21 more grain than the highest yielding cultivar developed before 1970. Seedling vigor and other phenotypical growth traits did not explain consistent yield differences between cultivars. These results suggest that modern spring wheat cultivars are adapted to certified organic environments. The phenotypical growth traits considered in this study are not suited as primary selection criterion for cultivars in certified organic environments.