The tomato industry is facing its "most serious ever threat" in the form of a potentially devastating pest.

Tuta absoluta, which is also known as the South American tomato moth, has been found in the UK this year for the first time. Tuta caterpillars target plants, making them unable to photosynthesise, or burrow deep into the fruit, laying eggs and rendering the tomatoes unsaleable.

So far, nine cases have been reported on UK nurseries and further incidences have been found in UK packhouses holding tomatoes imported from abroad.

Since the first reported European incidence in Spain two years ago, tuta has spread to all European tomato-producing nations and has caused widespread crop losses in the Mediterranean countries.

"Tuta is probably the most serious threat we've ever had," said executive officer for the British Tomato Growers' Association, Gerry Hayman. "We need to do something, sharp."

Urgent discussions have been scheduled for January, when growers will formulate their defence against the pest. If its progress is not checked it could cause significant supply problems, warned horticultural consultant Rob Jacobson.

"The big worry for individual growers is that it could interrupt supplies to supermarkets," he said. "If caterpillars are found inside fruit, clearly they won't want to take produce from that supplier."

While pesticides were one option, there was concern over the cost implications involved, Jacobson added. "It's yet another problem when margins are very small and there isn't scope for substantial production cost increases or loss of yields. The industry has every right to be worried about this."

The Food and Environment Research Agency was also closely monitoring the pest, said Fera plant health entomologist Dominic Eyre. "We'll be trying to make everyone aware of the problem on new crops in 2010. We'll continue to monitor it and try to get on top of it, as well as communicating with the Spanish."