BREEDING FOR HEAD BLIGHT (FUSARIUM SPP.) RESISTANCE IN WHEAT: DEVELOPMENT OF A MYCOTOXIN-BASED SELECTION METHOD OF SEEDLINGS

M. Lemmens, A. Reisinger, H. Bürstmayr, P. Ruckenbauer
An increase in incidence of Fusarium head blight (FHB) on wheat has been reported in Austria during the last years (Zwatz, 1987). Nine different Fusarium spp. have so far been isolated from wheat in Austria, the most important of which are F. graminearum (Adler et al., 1990) and F. culmorum (Zwatz, 1987). Infestation of the ear has several consequences: 1) yield reduction, 2) reduction of baking quality, 3) reduction of seed quality and 4) production of mycotoxins. A large variation in FHB resistance of wheat has been reported (Mielke, 1988; Saur, 1991, Snijders, 1990a; Zwatz, 1987). The number of genes governing resistance varies from 2 to 3 (3 dominant genes in cultivar ‘Shinchunaga’ (Nakagawa, 1955); 2 to 3 genes in cultivar ‘Sumey-3’ (Zhou et al., 1987)) up to 6 (in 10 SVP winter wheat cultivars (Snijders, 1990b)) and more (polygenic (Gocho, 1985; Gu, 1983)). Highly resistant varieties such as ‘Nobeokabozu’ (Japan), ‘Sumey-3’ (China) and ‘Frontana’ (Brazil) have been described (Teich, 1989; Zhou et al., 1987; Mesterhazy, 1989), but complete resistance was not found (Naito et al., 1984; Mielke, 1988).

It was decided to start a Fusarium resistance breeding program in cooperation with Austrian breeders to improve the FHB resistance of their breeding material. In order to decrease the amount of field inoculations, a study was carried out to develop a simple laboratory method to examine FHB resistance of wheat breeding material. In literature several methods are described to select plants with increased level of disease resistance using toxic metabolites produced by Fusarium as selection agent. The toxins produced by plant pathogens can be classified into two categories: host-specific and nonhost-specific, on the basis of selective phytotoxicity to compatible and noncompatible hosts. A host-specific toxin selectively damages only those plant varieties that are susceptible to the pathogens. Both F. graminearum and F. culmorum produce several nonhost-specific toxins, the most important of which are the trichothecenes deoxynivalenol (DON) and 3-acetyldeoxynivalenol. They probably play a role in the aggressiveness of the pathogen and promote disease development and colonization (Snijders and Krechting, 1992). These trichothecenes inhibit eukaryotic protein synthesis by blocking the peptidyl transferase step (Carter et al., 1980). It has been reported that plants tolerant to these toxins have an increased resistance to FHB (Snijders and Krechting, 1992). Either crude toxic metabolite extracts (Lijuan et al., 1991; Fadel and Wenzel, 1993) or highly purified toxins have been used (Wakulinski, 1989; Wang and Miller, 1988). Selection was carried out at the level of germinating seeds and seedlings (Shimada and Otani, 1990; Wakulinski, 1989), callus (Lijuan et al., 1991), coleoptiles (Wang and Miller, 1988) or microspores (Fadel and Wenzel, 1993). Good correlations between in vitro tests and FHB resistance have been reported (Wang and Miller, 1988; Wakulinski, 1989; Lijuan et al., 1991).

Lemmens, M., Reisinger, A., Bürstmayr, H. and Ruckenbauer, P. (1994). BREEDING FOR HEAD BLIGHT (FUSARIUM SPP.) RESISTANCE IN WHEAT: DEVELOPMENT OF A MYCOTOXIN-BASED SELECTION METHOD OF SEEDLINGS. Acta Hortic. 355, 223-232
DOI: 10.17660/ActaHortic.1994.355.25
https://doi.org/10.17660/ActaHortic.1994.355.25

Acta Horticulturae