Registration of Maize Germplasm Lines Tx736, Tx739, and Tx740 for Reducing Preharvest Aflatoxin Accumulation

Maize ( Zea mays L.) production in Texas, the southern United States, and much of the developing world is constrained by preharvest contamination from aflatoxins—potent mycotoxins produced by the fungus Aspergillus flavus . When consumed, aflatoxin can lead to impaired growth, liver cancer, or death of both humans and livestock. Because of these effects, the presence of this mycotoxin is tightly regulated in the U.S. food supply. No complete resistance to A. flavus or aflatoxin is known to exist in maize; however, multiple quantitative traits and some sources of resistance have been identified. We propose the release of three maize lines that demonstrate reduced preharvest aflatoxin accumulation. Tx736 (Reg. No. GP‐578, PI 662937) is a germplasm line derived from modified pedigree selection of a cross between Tx772, a line with reduced aflatoxin accumulation, and T246, a temperate line with good yield and Texas adaptation, backcrossed to Tx772 once. Lines Tx739 (Reg. No. GP‐579, PI 662938) and Tx740 (Reg. No. GP‐580, PI 662939) were selected by pedigree methods from S 3 plants selfed out of heterotic groups A, C, and E from Agricomseeds (Santa Cruz, Bolivia). These three lines were field tested as lines per se and as testcross hybrids with introduced inoculation in multienvironmental field trials. In trials, these lines and hybrids had between 30 and 73% lower aflatoxin content than commercial checks. These germplasm lines will serve as unique sources for novel traits and alleles that reduce aflatoxin in elite temperate and subtropical maize.