Improvement In Genetic Yield Potential of Semi-Dwarf Wheat In the Great Plains.

Recently, private companies and public entities have made significant investments and improvements to their wheat (Triticum aestivum L.) breeding programs.   Because of this increased interest, genetic improvement made in wheat through traditional plant breeding needs to be analyzed.  Many studies have noted the significant yield improvement from tall cultivars to semi-dwarf cultivars, but no studies have documented improvements made from earliest the semi-dwarfs to present-day cultivars.  Thirty cultivars were tested including 2 tall varieties (Kharkof, 1921 and Triumph 64, 1964), and 28 semi-dwarf cultivars spanning the period from 1971 (TAM 101) to 2008 (Jackpot and TAM 401).  Cultivars were tested together in 2010 and 2011 over eleven locations across Oklahoma, Kansas, and Texas with adequate disease protection and fertilizer. Experimental design was a split-plot design with fungicide treatment as the main plot and cultivar as the sub-plot with three replications per location.  Results for testing from both years will be presented.