Quality and value of organic grain from contrasting breadmaking wheat varieties and near isogenic lines differing in dwarfing genes.

Comparisons of Maris Widgeon, an old taller breadmaking variety, were made with more modern varieties of wheat in eight successive field experiments between 1987/88 and 1994/95 at Harnhill Manor Farm, Cirencester, Gloucestershire, U.K. for grain yield, specific weight, protein concentration, SDS-sedimentation volume and Hagberg falling number. The effect of quality of the grain on financial value was investigated by applying a range of penalties for insufficient protein, Hagberg falling number and specific weight. Values for feed and breadmaking quality wheat were also varied. For all of the different pricing scenarios, grain from Maris Widgeon was of lower value than that from the most modern variety. The higher protein concentration of Maris Widgeon, in comparison with Hereward, was insufficient to compensate for lower yields and Hagberg falling numbers. Reduced height genes (Rht1 and Rht2) in isogenic lines of Maris Widgeon, studied in one field experiment, increased grain yield and Hagberg falling number but reduced protein content. Interactions of variety with other factors relevant to organic systems were also investigated namely undersowing (four seasons), defoliation by mowing or sheep grazing in Spring (three seasons), and sowing date (two seasons) but these factors had little impact on the relative grain performance of the varieties studied.