GE corn test seen as biotech victory

CHICAGO - The main type of genetically engineered corn used in the United States poses no threat to one common butterfly, new research claims.

Scientists at the University of Illinois monitored populations of black swallowtail butterflies by a field planted with genetically altered corn and found no relationship between the insects' mortality rate and pollen from the corn.

"We found that many caterpillars died but not, as far as we could tell, due to anything connected to the corn or the corn pollen," said May Berenbaum, head of the university's entomology department.

May Berenbaum said the field and laboratory studies found spiders, carnivorous insects and other environmental factors to be the main causes of death.

The findings - published last week in the Proceedings of the National Academy of Sciences - differ greatly from a Cornell University study last year which said laboratory tests showed pollen from genetically altered corn harmed monarch caterpillars.

The Cornell report provided fuel for opponents of gene-altered crops, with some adopting the monarch butterfly as a symbol of protest.

The Illinois study - which in the field looked at a GM variety known as Bt corn - has been hailed by an industry trade group as a victory for biotechnology.

"This new study, conducted under actual field conditions, should help clip the wings of last year's stories hypothesising negative effects of Bt corn on monarch butterflies," said Dr L.Val Giddings, vice-president for food and agriculture of the Biotechnology Industry Organisation.

Bt corn is produced by Pioneer Hi-Bred International, a subsidiary of DuPont. The plants carry a gene from a soil bacterium that enables them to produce their own insecticide.

The Bt technology, which was used in 20 per cent of US corn plantings this summer, was designed to shield plants from the European corn borer, a costly pest. But last year's Cornell study sparked fears about the effects of such GE corn on non-target insects.

May Berenbaum said that one conclusion of the new study was that growers might be able to customise their corn crop by using different genetic modifications, known as "events."

"There are ways to reduce the risk to non-target organisms at the very least by event selection," she said, just as farmers customise use of conventional insecticides depending on environmental risks.

Her team has focused on the black swallowtail because her department has years of expertise with the species, which is common throughout eastern North America.

Like the monarch, the black swallowtail feeds on plants along the strips between cornfields and roads.

- REUTERS

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