- http://www.agbioworld.org, http://agbioview.listbot.com
I'd like to see my corn flakes box bear a label guaranteeing
"low-mycotoxin, Bt corn--> reduced cancer risk"; many folks are bemoaning
the lack of obvious consumer benefits to the first round of GE crop
releases. Well, here is a big one. If cereals can be labelled extolling
the virtues of fibre content, surely, reduced fumonisin levels might catch
consumers' attention. BOB
(the following forwarded from Agnet 26 Apr '00)
BT CORN: LESS INSECT DAMAGE, LOWER MYCOTOXIN LEVELS, HEALTHIER CORN
April 26, 2000
USDA - ARS News Service
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
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.