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Study shows GM maize kills butterflies

- 23 August 2000
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23 August 2000



Study shows GM maize kills butterflies


By FWi staff

NEW research confirms that pollen from genetically modified maize can kill the larvae of the American monarch butterfly.

In a two-year study scientists at Iowa State University discovered many caterpillars died when fed with milkweed sprinkled with GM pollen from Bacillus thuringiensis (Bt) maize.

This backs research last year which suggested Bt maize may produce pollen toxic to the monarch butterfly.

The Bt maize developed by Swiss life sciences company Novartis contains a natural insecticide to kill the corn borer pest which damages maize.

A spokesman for Greenpeace told the BBC Radio Four Farming Today this showed the crops should be banned as risk had not been assessed.

Greenpeace has called for the US Environmental Protection Agency to cancel its registration of Bt crops.

But Steven Smith, chief executive officer for Novartis Seeds UK told Farming Today that tests did not take place in a realistic environment.

He said the research was not conducted as a field study but as a laboratory test and that caterpillars were only offered milkweed to eat.

Milkweed was not common in maize fields, larvae feeding and pollen shedding may not coincide, pollen would be washed off and would only fall on top leaves, he added.

However, he did not dispute that the larvae were killed by the pollen which is toxic to certain caterpillars as well as corn borers.

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