An international team of scientists reports that it has been able to suppress the aflatoxin-producing fungus and generate peanuts that are near-immune to aflatoxin contamination. The discovery has the potential to improve food safety and reduce losses caused by aflatoxins. Results were published last month in the Plant Biotechnology Journal.
Aflatoxins pose a major risk to human and animal health worldwide. The molds, Aspergillus flavus and Aspergillus parasiticus, which infect peanuts, maize, and cottonseed, produce toxins that suppress the immune system and can hinder growth in children. The fungus can also stay dormant in soil for years..
Dilip Shah, Ph.D., principal investigator at the Donald Danforth Plant Science Center, and his team transferred defensins from alfalfa and the Mediterranean clover to the DNA of an Aspergillus-susceptible peanut variety widely grown in Africa and India, which allowed the peanut to stop the fungus from infecting the plant. The team then transferred small RNA molecules from the Aspergillus fungus that is involved in the aflatoxin synthetic pathway. The nuts produced these RNA molecules during fungal attacks and inactivated target genes responsible for aflatoxin synthesis.
"Plant defensins exhibit potent antifungal activity against several economically important fungal pathogens and it is exciting to see successful application of this technology for reducing the pre-harvest infection by Aspergillus and alleviating the burden of mycotoxins in genetically modified groundnut. If deployed commercially, this technology has significant potential to contribute to food safety in the under-developed and developing countries where mycotoxin contamination of groundnut, maize, chili and cottonseed pose a major threat to human and animal health," explained Shah.
Image: Peanuts that are near-immune to aflatoxin contamination have been developed, offering a panacea for serious food safety, health, and trade issues. Image courtesy of Fotolia, Donald Danforth Plant Science Center.