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ARS
Scientists Present Findings at Society MeetingBy Jan Suszkiw August 11, 2003Protecting corn crops with
"flower power" is Eric Johnson's focus as one of about 20
Agricultural Research Service scientists
who will discuss their work and latest findings Aug. 9-13 at the Phytochemical
Society of North America's (PSNA) annual meeting in Peoria,
Ill. A research associate at ARS' National
Center for Agricultural Utilization Research in Peoria, Johnson is
conducting studies aimed at developing corn plants that carry genes for making
anthocyanins. These are pigments that, depending on pH conditions, impart red
and purple color to many kinds of flowers, fruits (visualize blueberries) and
vegetables. Johnson's anthocyanin interests aren't of the aesthetic kind, however. Rather, he is following up on prior research suggesting large amounts of
anthocyanins can deter some insects from feeding. Specifically, Johnson set his
sights on the fall armyworm and corn earworm. As a caterpillar, the latter
insect costs U.S. corn growers $1 billion annually in crop losses and chemical
control expenses. At the ARS center's
Crop Bioprotection Research
Unit, Johnson is feeding the caterpillars a diet they'd normally benefit
from, except for one secret ingredient: a 1,000-parts-per-million dose of
delphinidin. It's one of several anthocyanins available commercially. During the PSNA's "Art Niesh Young Investigator Mini Symposium" on Monday, Aug. 11, Johnson will report his observations to date. These include a 60 percent decrease in the weight of armyworms fed a diet containing delphinidin, compared to a control group. Chemical insecticide is now used to fight this pest, as well as the corn earworm. But Johnson's work could eventually lead to new corn hybrids whose silks mass-produce the anthocyanin pigments as a built-in defense against the caterpillars before they chew their way to the kernels. ARS entomologist Pat Dowd, the lead scientist on the work, is especially interested in stopping the pests from spreading fungi that can sometimes contaminate corn kernels with toxins such as aflatoxin and fumonisins, which are harmful to humans and livestock. ARS is the U.S. Department of
Agriculture's chief scientific research agency. U.S. Department of Agriculture |