'Plant Breeding: Sustaining the Future' Abstracts of the XVIth EUCARPIA Congress, Edinburgh, Scotland, 10-14 September 2001 GERMPLASM EVALUATION IN THE NORTHERN CORN BELT M.J. CARENA Department of Plant Sciences, North Dakota State University, Fargo, ND 58105, USA

The most important decision of a breeder is the choice of germplasm that will produce elite material for several generations. The objective of this project was to evaluate and screen potential germplasm sources for early maturity regions. Ten corn synthetic populations and their crosses (S0 generations) were evaluated in experiments arranged in a randomized complete block design in 2000. Each experiment was conducted at five North Dakota environments. The only irrigated location (Oakes) has shown grain yields ranging from 6.3 Mg Ha^-1 to 19.4 Mg Ha^-1. Synthetic corn populations have demonstrated equal or better (P<=0.05) performance than two commercial checks. The potential of synthetic populations was expressed in hybrid combinations demonstrating the importance of heterosis. Selected populations will be classified into unique heterotic groups.