Irrational public debates and scare stories about science will damage the development of research in Britain if left unchecked, the prime minister believes.

Speaking to the Guardian ahead of a speech on science, Tony Blair said that he would stand up for science against the distrust engendered by historic problems such as the BSE crisis and the scare over the MMR vaccine.

"We've got to understand the importance of science to the future of the economy and to the future of society," he said. "In my view, for the next generation, development of science is as important as economic stability for future prosperity."

His talk in Oxford today is part of a series of speeches on securing Britain's future. Mr Blair will raise issues on public trust in science and what he sees as hurdles to attracting more young people to subjects such as physics, chemistry and engineering.

"I want to stick up for science and say why it's important and why we have rational debates about scientific issues rather than allow irrational debate," he said. "We've made that a very strong part of what the government's about and will continue to do so. The damage it can do otherwise is rather frightening."

He cited the scare over the triple vaccine, MMR, in recent years and the BSE epidemic among cattle in 1990s as examples. "Scientists got the blame [for BSE] and I think that's ludicrous. It wasn't scientists feeding rubbish to the animals, it was scientists who had to investigate and finally did discover what was going on."

Upcoming technologies such as genetics would throw up plenty of ethical issues, which would need careful consideration by a scientifically-literate public.

Public distrust in the past had led to a loss of research expertise in genetic modification. "The GM thing shows you can very suddenly lose a whole swath of the public ... [but] if you look around the world at the moment, bioscience is obviously where we should be heading."

Mr Blair argued that the potential for GM crops in Britain was limited for practical reasons. "If you look around the world to where GM crops are being developed most, it's where you have vast farming tracts. The future agriculture for this country is more likely to be in organic niche farming."

But he added that this should not prevent the UK from taking a lead on research in the area.

The speech will also outline how to encourage young people to consider taking science subjects at school and university. "There is a point in getting people enthused and saying, this is where the glittering prizes are. A lot of young people are interested, but they don't see it as a career except as a boffin. They don't see it as a career in which you develop one of the leading edge companies. They see science as what you do in a laboratory."