Nitrogen Use and Biomass Distribution of Winter Wheat Populations Selected from Grain-only and Dual-purpose Systems. (5811)
Authors:
C.T. MacKown* - USDA-ARS Grazinglands Research Lab B.F. Carver - Oklahoma State University, Stillwater
Abstract:
Southern Great Plains producers grow winter wheat (Triticum aestivum L.) primarily as either a grain-only (GO) or a dual-purpose (DP, grazing plus grain) crop. Traditionally, cultivars used for both production systems are developed in a GO system. Because DP grown wheat may forfeit gains in grain yield accrued for GO-developed cultivars, we evaluated N and biomass traits for 12 sets of
sub-populations (each set a unique pedigree) to test benefits of making selections from a DP system. Sets came from F2 sources and contained a base (B) F3 bulk population and F5 bulk populations mass selected from the F2 within GO and DP systems. The 12 sets of sub-populations were evaluated in GO and DP systems in 2001-02 and 2002-03. At anthesis, main effects (year, system, pedigree, selection environment) were significant for culm dry wt. and N, and flag leaf dry wt. Among selections, differences for these traits were small (2.0 - 3.5%) with no difference between GO and DP selections which were slightly less than the B selection, while differences among pedigrees were large (21 - 30%). At maturity, differences (7.6 – 20%) for culm, grain and kernel dry wt., HI, N uptake, grain N, and NHI occurred among pedigrees, while differences among selections were smaller (1.4 – 4.5%) and significant for only culm, grain and kernel dry wt., and N uptake. Selections made from the DP environment performed similar to those from the GO environment when grown in either production system.
Speaker Information: Charles MacKown, USDA-ARS Grazinglands Research Lab, 7207 W. Cheyenne St, El Reno, OK 73036; Phone: 405-262-5291; E-mail:
Session Information: Wednesday, November 3, 2004, 4:00 PM-6:00 PM Presentation Start: 4:00 PM (Poster Board Number: 0912)
Keywords: wheat; nitrogen use; forage plus grain; dual-purpose