Breeding for Fusarium Head Blight Resistance in Wheat

Abstract

The resistance to FHB is race non-specific and gives protection against several Fusarium species. The resistance is a complex phenomenon; many factors contribute to the final result. An indirect way to select plants for FHB resistance does not generally exist via seedling blight, leaf blight or crown rot resistance; in some cases these traits occur in one plant. Breeding for FBH resistance in most cases needs to test the FHB reaction. Breeding is possible: a number of highly resistant winter wheat lines with resistance to other diseases show this. More knowledge about genetics will provide new ways to establish high FHB resistance in the new cultivars. FHB occurs in all wheat production areas. However, a more powerful occurrence is recorded on warm and humid summer territories. It is a typical disease attacking the crop irregularly. Many years may pass without losses and under favourable conditions the farmers may suffer devastating losses. This is not only a decrease in yield, baking quality or feeding value, but because of the toxins produced by the pathogens, the remaining yield cannot be used for any purpose. As fungicide control is expensive and not always effective enough the breeding of resistant cultivars seems to be the most important task. It has to be clarified how far the toxin contamination can be reduced by more resistant or resistant cultivars. Recently several reviews were published detailing the problems of breeding (Snijders, 1994; Parry et al., 1995; and Miedaner, 1997). Therefore, we summarise several results and concepts that make the nature of resistance more understandable and allow to develop a better breeding technology. Resistance research needs reliable test methods. These were developed in the past 30 years and now provide a solid basis of research and breeding (Mesterházy, 1989; 1995; Mesterházy et al., 1999). The resistance structure to FHB is complex. For the physiological factors seven. For morphological traits five, and we have to consider also four resistance traits in other organs than head. This complexity can be problematic for breeders to consider more than ten resistance traits in a program and FHB is only one trait.