From isjd@ars-grin.gov Wed Apr 26 11:55:49 2000 Date: Wed, 26 Apr 2000 06:03:40 -0400 From: ARS News Service To: ARS News List Subject: Bt Corn Has Lower Toxin Levels STORY LEAD: Bt Corn: Less Insect Damage, Lower Mycotoxin Levels, Healthier Corn ___________________________________________ ARS News Service Agricultural Research Service, USDA Kim Kaplan, (301) 504-1637, kkaplan@asrr.arsusda.gov April 26, 2000 ___________________________________________ Bt corn that has been genetically modified to prevent damage by European corn borers may also be less likely to harbor mycotoxins, toxins produced by fungi on corn ears, according to an Agricultural Research Service entomologist. Mycotoxins like fumonisin, a potential cancer-causing agent often found at elevated levels in insect damaged kernels, are both a health issue and an export issue. European and Asian markets can refuse to import U.S. corn because of what they rate as unacceptable levels of mycotoxins. Scientists have suspected higher mycotoxin levels may follow increased insect damage, but ARS entomologist Patrick F. Dowd found fumonisin levels 30- to 40-fold lower in Bt corn than in non-Bt varieties in Illinois cornfields. Bt stands for the biopesticide Bacillus thuringiensis. Environmental conditions and the specific Bt corn hybrid play roles in the actual amount of reduction seen, but corn varieties that expressed the Bt protein throughout the plant rather than in specific areas were the least likely to have significant fumonisin levels, according to Dowd, who is with ARS' National Center for Agricultural Utilization Research in Peoria, Ill. ARS is the U.S. Department of Agriculture's chief in-house research agency. While Bt corn is modified mainly to resist European corn borers, Bt corn also showed lower levels of mycotoxins when corn earworms were present in fields, although not as significant a reduction as when European corn borers were the primary insect pest. This may encourage the creation of corn varieties with more resistance to a variety of insects in order to provide more protection from mycotoxins. Small plot studies by Iowa State University plant pathologist Gary Munkvold appear to confirm Dowd's findings. ___________________________________________ Scientific contact: Patrick Dowd, ARS National Center for Agricultural Utilization Research, Peoria, Ill., phone (309) 681- 6242, fax (309) 681-6686, dowdpf@mail.ncaur.usda.gov. ___________________________________________ This item is one of the news releases and story leads that ARS Information distributes on weekdays to fax and e-mail subscribers. You can also get the latest ARS news on the World Wide Web at www.ars.usda.gov/is/pr/thelatest.htm. * Feedback and questions to ARS News Service via e-mail: isnv@ars-grin.gov. * ARS Information Staff, 5601 Sunnyside Ave., Room 1-2251, Beltsville MD 20705-5128, (301) 504-1617, fax 504-1648.