SELECTION RESPONSES IN WINTER WHEAT INDUCED BY GRAIN-ONLY AND DUAL-PURPOSE MANAGEMENT SYSTEMS

Authors: CARVER, BRETT - OKLAHOMA STATE UNIV.; MACKOWN, CHARLES

Submitted to: Agronomy Society of America, Crop Science Society of America, Soil Science Society of America Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/16/2005
Publication Date: 11/6/2005
Citation: Carver, B.F., Mackown, C.T. 2005. Selection responses in winter wheat induced by grain-only and dual-purpose management systems [abstract]. Agronomy Society of America, Crop Science Society of America, Soil Science Society of America Meeting. Paper No. 5672.

Interpretive Summary: Abstract Only

Technical Abstract: Each year, producers will plant 60 to 75% of Oklahoma's wheat acreage with the intent to graze it in the winter months before harvesting the crop for grain. Cultivar choices for this dual-purpose (DP) management system come almost entirely from cultivars bred in a grain-only (GO) management system. Genes selected for high yield in a GO system may not confer the same yield advantage in a DP system. Field experiments were conducted to test that hypothesis using 24 sets of winter wheat populations. Each set, with a unique pedigree, was derived from the same F2 source and contained a base F3 bulk population and F5 bulk populations mass selected from the F2 for three consecutive generations within either a GO or DP system. Grain yield and related agronomic traits were measured in these populations for 3 yr in both management systems. Populations mass selected in the DP system tended toward a more prostrate vegetative growth habit and appeared to tolerate grazing better than those selected in the GO system. Differences between selected populations were detected for grain yield when measured in the DP system, though yield differences were not so apparent in the GO system. At least for the bulk progeny, the results showed an adaptive advantage in the DP environment for those populations originally selected in that environment.