July 8, 2009 — Scientists are reporting for the first time that the use of weed
killers in farmers’ fields boosts the nutritional value of an important
food crop. Application of two common herbicides to several varieties of
sweet corn significantly increased the amount of key nutrients termed
carotenoids in the corn kernels, according to a study scheduled for
publication in the July 22 issue of ACS’ Journal of Agricultural and Food Chemistry, a bi-weekly publication.
In the new study, Dean Kopsell and colleagues note that farmers grow
about 240,000 acres of sweet corn in the United States each year,
making it an important food crop. Corn is among only a few vegetable
crops that are good sources of zeaxanthin carotenoids. Consuming
carotenoid-rich vegetables may reduce the risk of age-related macular
degeneration (a leading cause of vision loss among older people), heart
disease, and cancer, the study notes.
The scientists exposed several varieties of sweet corn plants to the
herbicide mesotrione or a combination of mesotrione and atrazine,
another commonly used weed killer, and harvested mature corn 45 days
later. Herbicide applications made the corn an even-better source of
carotenoids, boosting levels in the mature kernels of some varieties by
up to 15 percent. It specifically increased levels of lutein and
zeaxanthin, the major carotenoids in sweet corn kernels, which studies
have linked to a reduced risk of age-related macular degeneration.
–News release courtesy of American Chemical Society