Fusarium head blight in wheat and mycotoxins

CHULZE, S.N

Mar del Plata

Congreso; Segundo Congreso Argentino de Fitopatologia; 2011

Asociacion Argentina de Fitopatologos

The Fusarium head blight  (FHB) of wheat is a growing treat to the world`s food supply because recent outbreaks in different  regions of the world  including Asia, Europe, Canada, North and South America. In Argentina, several FHB  epidemics occurred in the last 50 years, causing yield losses and price discount due to reduced seed quality. Gibberella zeae (Schwein.) Petch (anamorph Fusarium graminearum Schwabe), lineage 7, within the Fusarium graminearum complex,  is the principal causal agent of  FHB in Argentina. Studies using vegetative compatibility groups (VCGs)  showed   that the genotypic diversity in G. zeae populations isolated from wheat in Argentina is high. The genetic structure of the G zeae populations  characterized. using  AFLP markers showed that these populations are genetically and genotipically diverse and that there is a significant amount of genetic exchange occurring between genetically proximate populations. By  a multiplex PCR assay of  Tri3, Tri7,and Tri13 and chemical analysis the trichothecene genotype and chemotype  of   F. graminearum  strains collected from three locations in Argentina  were evaluated. Most strains (92%) had the 15-ADON genotype, with the remaining strains having the deoxynivalenol/nivalenol (DON/NIV) genotype.   The strains with DON/NIV genotype produced DON when analyzed chemically. The accumulation of  dexynivalenol (DON) in the grain is intimately related to the development of the disease in the field . Therefore, the current strategy to manage DON in cereals is to manage FHB. Biological control offers an additional strategy and can be used as  part of an  integrated   management of FHB. References Palazzini, J.M, Ramirez, M.L., Alberione, E.J, Torres, A.M, Chulze, S:N (2009) Biological Control 51:370-376 Ramirez, M.L., Reynoso, M.M., Farnochi, M.C., Torres, A.M., Leslie, J.F., Chulze, S.N.(2007) Food Additives and Contaminants 24:1115-1120 Reynoso, M.M., Ramirez,M.L., Torres, A.M., Chulze, S.N (2011) Internacional Journal of Food Microbiology 145: 444-448.