Submitted to: Aflatoxin Elimination Workshop Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 20, 1999
Publication Date: N/A
Technical Abstract: A potentially effective and highly desirable method of reducing aflatoxin contamination of corn grain is the use of genetically resistant hybrids. This investigation was conducted to determine the level of resistance to aflatoxin accumulation in corn hybrids currently available to farmers in the South. A second objective was to compare the level of resistance to aflatoxin accumulation in commercially available corn hybrids to that of crosses among germplasm lines developed and released as sources of resistance to aflatoxin accumulation by USDA-ARS scientists at Mississippi State, MS and Tifton, GA. In 1998, the hybrids evaluated were selected from those entered in the Mississippi Hybrid Corn Yield Trials. In 1999, several companies contributed hybrids specifically for evaluation for resistance to aflatoxin accumulation. Hybrids were inoculated 7 days after midsilk by injecting an Aspergillus flavus spore suspension containing 300,000,000 conidia into the side of the ear. Isolate NRRL 3357 was used as inoculum. Ears were harvested approximately 63 days after midsilk, and the level of aflatoxin was determined using the Vicam Aflatest (Watertown, MA). Aflatoxin levels were extremely high in the Mid South in 1998, and aflatoxin levels in this investigation ranged from 70 to nearly 12000 ppb. Mp313E x Mp494 had the lowest level of aflatoxin. In 1999 when conditions were less conducive to aflatoxin accumulation, aflaoxin levels ranged from 4 to 1062 ppb. Mp313E x Mp715 had the lowest level of aflatoxin. In general crosses with Mp313E, Mp420, and Mp715 as parents exhibited the highest levels of resistance.