As sources of fusarium head blight (FHB, scab) resistance have existed for decades, the most important breeding problems have been the lack of information about the nature of resistance, and the lack of reliable methods to test it. Methods have been evaluated during the past 25 years, and their critical points are largely known. Spring wheat resistance sources have been incorporated into winter wheats, producing a large number of lines with excellent resistance to FHB. Toxin accumulation only partly correlates with susceptibility. Data from replicated trials indicate that some genotypes have very limited amounts of deoxynivalenol (DON) in comparison with infection severity of the grains; however, in the most resistant lines, none, or only a very slight infection, occurs. In these cases, DON contamination has never been detected; therefore, we can be optimistic in breeding for highly resistant cultivars to scab. The major problem is to incorporate this knowledge into a practical breeding process, and combine high FHB resistance with other important traits, including resistance to other diseases, high yield potential, and good grain quality.

English

9806|AGRIS 9802

Jose Juan Caballero

CIMMYT Publications Collection