Aflatoxin Accumulation in BT and Non-BT Maize Testcrosses

摘要

The accumulation of aflatoxin, produced by the fungus Aspergillus flavus in maize, is a chronic problem in the southeastern United States. Its presence in grain greatly reduces its value and marketability. Aflatoxin accumulation is frequently associated with high temperatures, drought, and insect damage. Ten maize germplasm lines, some selected for resistance to aflatoxin accumulation, were crossed to transgenic (transformed with genes from Bacillus thuringiensis Berliner (BT) and expressing the Cry1Ab protein) and non-transgenic versions of LH287. Testcrosses were evaluated for ear damage from insect feeding and aflatoxin accumulation. Ear damage caused by insect feeding and aflatoxin accumulation was significantly less in BT than non-BT testcrosses. The germplasm line × BTon-BT interaction was not significant. Three lines selected for resistance to aflatoxin accumulation (Mp313E, Mp717, Mp04:97) exhibited the lowest levels of aflatoxin whether crossed to the BT or non-BT versions of LH287. Neither the levels of aflatoxin accumulation nor ear damage differed significantly between the BT and non-BT versions of these hybrids. This indicates that adding BT to hybrids produced from Mp313E, Mp717, or Mp04:97 would not be expected to increase resistance to aflatoxin accumulation.