Science - November 10, 2005

Wingless ladybird deals with lice

It looks a bit helpless without wings, but Dr Peter de Jong of the Laboratory of Entomology does not think that the wingless ladybird is to be pitied. ‘It is not in pain and it doesn’t know any better.’ De Jong believes that the wingless beetle is more effective at biological control than its winged counterpart.

Ladybirds eat thousands of lice in their lifetime. People with lice problems in their crops find ladybirds useful, but are dependent on the wiles of the beetles. If a ladybird thinks that there is more to eat elsewhere, it flies away. Therefore farmers have to release new ladybirds regularly to keep the lice under control. Researchers in Wageningen and Leiden are working on a ladybird that cannot fly away.

‘Ladybirds without wings are found in the wild, but only rarely,’ explains De Jong. ‘In ten years we have only found two wingless ladybirds. We are using one of them to do further breeding. We hope to only have to release one lot of ladybirds once we have set up a stable system where there are enough lice for the ladybirds to eat and be satisfied, but not so many that the crop is damaged.’

The researchers are also considering the question whether a wingless ladybird is a pathetic creature. ‘In the end the question is important because of whether the development will be deemed acceptable. If people regard wingless ladybirds as malformed creatures to be pitied, it could lead to problems. We think that we have good arguments in our favour. We are developing an environment-friendly and effective way of dealing with lice without having to import exogenous natural enemies, and without using genetic manipulation. We hope that the advantages to consumers will outweigh the less attractive appearance of this ladybird.’

The research is financed by the STW technology fund and Koppert, a leading biological crop protection company. / KV

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