Mycotoxins in Australia: biocontrol of aflatoxin in peanuts

Abstract

The major mycotoxin problem in Australia is the formation of aflatoxins in peanuts by Aspergillus flavus and A. parasiticus. This is controlled by good farm management practice, segregation into grades on aflatoxin content at intake to shelling facilities, colour sorting and aflatoxin assays. A second problem is the potential presence of ochratoxin A in grapes and grape products, resulting from infection by Aspergillus carbonarius. Good quality control before and during wine making ensures ochratoxin A is kept to very low levels, but in dried vine fruit, ochratoxin A levels may be higher. Biocontrol by competitive exclusion has been developed as the most promising means of controlling aflatoxins in peanuts. Some details of the process are given, including some basic laboratory experiments.

Scientific information on mycotoxins and natural plant toxicants

“…The greatest successes to date have been achieved with this approach to reduce AF contamination in cotton (Cotty, 1994), peanuts (Dorner et al, 1998;Dorner, 2004Dorner, , 2008Pitt and Hocking, 2006) and more recently in maize (Abbas et al, 2006). Two products of nontoxigenic strains have received U.S. Environmental Protection Agency (EPA) registration as biopesticides to control AF contamination in cotton and peanuts in several states of the USA (Dorner, 2004).The selected strains could be tested against A. nidulans and A. versicolor, but specific trials are needed.…”

Genetic Analysis of the Aspergillus flavus Vegetative Compatibility Group to Which a Biological Control Agent That Limits Aflatoxin Contamination in U.S. Crops Belongs

“…This SNP also exists in several other VCGs, but the distribution among other strains of YV36 other than AF36 is unknown, and its stability in treated fields has not been examined. Molecular characterization of fungal biocontrol agents is desirable in order to monitor isolates postapplication, especially in the case of biological control agents that may persist for extended periods of time and are expected to contribute to long-term biocontrol strategies (28,29).…”

Biocontrol of toxigenic strain of Aspergillus flavus isolated from the root tubers of safed musli (Chlorophytum borivilianum Sant. F) using its rhizospheric mycoflora

“…Even the non-toxigenic strains of Aspergillus flavus could be used to displace toxigenic strains and reduce aflatoxin contamination. Their bio-control potential has already been provedin various studies (Dorner, 2004;Cardwell and Henry, 2004;Abbas et al, 2006;Pitt and Hocking, 2006;Dorner, 2008;Yin et al, 2008;Tran-Dinh et al, 2013 andPitt et al, 2015). Similarly, Azziz et al (1997) In a very similar study by Roy et al (2008), the antagonistic interaction between toxigenic strains of A. flavus and co-existing fungi of maize rhizosphere was observed.…”