Methods for characterization of preharvest sprouting resistance in a wheat breeding program

Preharvest sprouting (PHS) can be a serious problem in western Canada resulting in economically important yield and grade losses for wheat producers. Improved PHS resistance is an important breeding objective and wheat breeders require effective and reliable methods to select for PHS resistance. The objective of this study was to evaluate whether differences exist between field and artificial weathering in the evaluation of PHS resistance in breeding lines and to determine whether sprouting scores are a good estimator of PHS resistance when compared to Hagberg falling numbers. Results suggest that both field and artificial weathering can be effectively used to screen for PHS resistance in wheat breeding lines. Although in this study, field weathering resulted in greater sprouting damage than artificial weathering, the ability to control conditions may make artificial weathering the more reliable test for PHS resistance in a breeding program. Mean sprouting scores greater than 7.5 consistently identified lines with low PHS resistance; hence, sprouting scores can be used to discard the most sprouting susceptible lines. However, falling numbers appear to be more reliable to evaluate the PHS resistance of advanced lines.