Biological control as a strategy to reduce the impact of mycotoxins in the food and feed chains

CHULZE , S.N

Beijing

Congreso; International Mycotoxin Conference 2014. Perspectives on the global prevention and control of mycotoxins; 2014

International Society of Mycotoxicology

Mycotoxins including aflatoxins, deoxynivalenol, fumonisins, ochratoxin A are among the main mycotoxins detected as natural contaminants in South America in different commodities as peanuts (aflatoxins) cereals (deoxynivalenol and fumonisins), grapes (ochratoxin A). Different strategies including crop rotation, tillage practices, fungicide application and planting less susceptible cultivars are used in order to reduce the impact of these mycotoxins in both the food and feed chains. The development of fungicide resistance in many fungal pathogens as well as rising of public concern on the risks associated with pesticides use led to the search for alternative environmentally friendly methods. Biological control of plant pathogens and toxigenic fungi offers an alternative that can complement chemical control in the frame of an integrated pest management (IPM) to reduce the impact of mycotoxins in the food and feed chains. Selection of native bacteria, yeasts and filamentous fungi have been done in order to evaluate them as potential biocontrol agents. Field trials showed that Bacillus subtilis RC 218 and Brevibacillus sp RC 263 were effective to reduce deoxynivalenol accumulation in wheat. Also the application of Clonostachys rosea isolates on wheat stubble reduced Fusarium colonization on the stubble. Bacillus amyloliquefaciens and Microbacterium oleovorans were also selected and showed good activity to control both Fusarium verticillioides growth and the accumulation of fumonisins at pre-harvest stage in maize. Control of toxigenic Aspergillus flavus and aflatoxin accumulation in peanuts was also achieved using a native atoxigenic Aspergillus flavus strain based on the competitive exclusion of the toxigenic strains. Kluyveromyces thermotolerans RCKT4 and RCKT5 were used as biocontrol agents to reduce the impact of Aspergillus section Nigri and ochratoxin A accumulation in grapes. Studies are on going on these selected biocontrol agents and to survey for new organisms and/or combinations of them to improve their affectivity.