QUALITY RESPONSE OF 12 HARD RED WINTER-WHEAT CULTIVARS TO FOLIAR DISEASE ACROSS 4 LOCATIONS IN CENTRAL KANSAS

Twelve hard red winter wheat cultivars were grown at four locations in central Kansas to evaluate the role of foliar fungal diseases on whea t end-use quality in 1995. Disease was allowed to develop naturally on control plots and was controlled partially on plots treated with a sy stemic fungicide. After harvest, wheat samples were evaluated for the impact of the disease complex (leaf rust, tan spot, speckled leaf blot ch) on physical grain quality, grain protein, milling properties, flou r absorption, and peak mixing time. Data were analyzed using a mixed m odel to account for random (location and block) and fixed (cultivar an d fungicide) effects. Location significantly influenced quality charac teristics except kernel size and peak mixing time. The magnitudes of v ariation among random effects on all quality characteristics were larg er for location than for the interactions between location x cultivar and location x fungicide. The fixed effects portion of the analysis re vealed that the cultivar x fungicide treatment interaction significant ly affected test weight, kernel protein, and flour absorption. Fungici de treatment resulted in significant increases in yield and kernel wei ght. Cultivar significantly affected all quality characteristics excep t kernel size and peak mixing time. Disease resistance exerted a signi ficant influence on yield and test weight. The economic benefit associ ated with improved wheat quality from fungicide treatment was variety specific. Three cultivars (TAM 107, Karl 92, and Ike), which account f or 50% of the 1997 planted wheat acres in Kansas, demonstrated positiv e improvements in test weight and protein in response to fungicide tre atment.