With dry weather, aflatoxin has been creating major headaches for peanut growers around Kingaroy in Queensland's Burnett district. Crop contamination was as high as 50-80 per cent last year, bringing price penalties and warnings of a mass grower exodus from the peanut industry.
(Industry quality control measures, costing at least $1 million annually across Australia, ensure that contaminated peanuts don't reach consumers.)
Scientists know soil moisture is a major influence in lowering aflatoxin levels - which is good news for irrigation growers - and that rotations with crops other than peanuts also help by reducing mould populations in soil.
Kingaroy farmers say this is not much help to them. In response, John Pitt of CSIRO's Division of Food Science and Technology has led research into biocontrol agents using non-toxic strains of the same moulds that cause aflatoxin. The research was supported by growers through the GRDC.
The results of field trials have been mixed and Dr Pitt says that more research is needed. While genetic engineering of peanut varieties may provide the answer in the long-term, other avenues need to be explored in the short-term.
Subprogram 2.4.1 Contact: Dr John Pitt 02 9490 8525