Biotech Updates

ARS Releases Corn Lines Resistant to Diseases, Aflatoxin Contamination

October 16, 2009

Researchers from the U.S. Department of Agriculture's Agricultural Research Service (ARS), in collaboration with colleagues from the Nigeria-based International Institute for Tropical Agriculture (IITA), have released six new inbred corn lines with resistance to aflatoxin contamination. Aflatoxins are among the most potent carcinogens known to man. They are produced by species of the Aspergillus fungus, most notably A. flavus, in groundnuts, cassava, yam and corn.

"These six lines have demonstrated good resistance against aflatoxin accumulation in laboratory and field tests," says Robert Brown, ARS plant pathologist. "They have also been shown to possess other commercially desirable corn traits, including resistance to southern corn leaf blight and southern corn rust."

The hybrid corn varieties are the product of a decade long collaboration between Brown and Abebe Menkir researcher at the IITA. The collaborators first screened and then combined the top aflatoxin-resistant lines found in the U.S.  with those found in Central and West Africa.

Brown has also identified a kernel protein, PR-10, produced by the Aspergillus-resistant corn varieties. In laboratory tests, this protein was found to destroy A. flavus RNA and to inhibit fungal growth. These results show that this protein may play an important role in corn resistance against A. flavus growth and aflatoxin contamination.