|Bjornstad, Asmund - UNIVERSITY OF NORWAY|
|Frey, Kenneth - IOWA STATE UNIVERSITY|
|Gullord, Magne - NORWAY|
|Buraas, Trond - NORWAY|
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 9, 2000
Publication Date: N/A
Interpretive Summary: Oats have highly variable yields from year-to-year in typical U.S. production environments. More stably high-yielding oat crops would help oat growers to maintain profitability and income stability. One approach to stabilizing yields is to select for oat lines that exhibit consistently high yields across diverse environments. We tested this approach by selection lines for three cycles based on their yields in the very diverse environments of Iowa, Idaho, and Norway. Our results showed that average yields increased across environments and within environments following selection. In addition, the stability of yield across diverse environments increased. Selected experimental lines from this program will be used as parents for U.S. oat cultivar development programs.
Technical Abstract: In order to test if selection can improve a population's adaptation to diverse environments simultaneously, three cycles of recurrent selection based on grain yield in Iowa, Idaho, and Norway were practiced in an oat (Avena sativa L.) Population developed from North American, Scandinavian, and wild species (A. Sterilis L.) Germplasm sources. Specific objectives were to determine if selection: increased mean yields across environments and within all environments; changed the genetic correlation of yields in different environments; and changed genetic variation for yield within the population. We evaluated 100 to 210 randomly-chosen families from each cycle of selection at three Iowa locations, in Idaho, and in Norway for two years. Grain yield within each location and mean yields across locations increased significantly over cycles of selection. Mean yields across locations expressed as a percent of the original populations mean increased dat a rate of 2.6% per year. Several families from the third cycle population exhibited both high mean yields across locations and consistently higher in the second cycle than in the original population. A trend of reduced genetic variation and heritability was observed in Iowa only. These results suggest that we successfully improved mean population yield both within and across locations, and yield stability across environments, and in developing families with outstanding adaptation to diverse environments.