Scientists racing to save the world's plants as global warming and human expansion threaten whole species fear a looming cash crunch may derail the ambitious project.

Already the Millennium Seed Bank has squirreled away 750 million seeds from 14,000 species of plants and trees, and the botanists are confident they will hit their target of 30,000 species or 10 per cent of the world's flora by 2010.

But then the money runs out. And for the seed bank's new boss Paul Smith, it is his biggest challenge.

"I want a large project collect 20 per cent of the world's flora by 2020," he said in his office near the town of Ardingly some 55 kilometres south of London.

"For that we need another 50 million pounds (US$87 million)," he said.

"That is just 2,000 pounds (US$3,480) per species. It is very good value. We are the biggest seed bank in the world: we have the facilities, the expertise and the network of international governments and institutions worldwide. Why waste it?"

Most of the original money for the project came from Britain's national lottery.

But it was only for the initial phase and Smith is casting around for new donors from Microsoft's Bill Gates to the UK Government and the European Union.

Dried, sorted and stored in underground vaults at -20 C, the seeds sit in glass jars in vaults, awaiting the day the scientists hope will never come when the species no longer exists in the wild.

"For many species, ex-situ banking is the only viable hope for saving the genes from extinction," Smith said.

"We may already be too late for some, and for others we know there are only a handful left in the wild but we have the seed here."

But as climate change and people decimate species and habitats, the bank is more than just a Noah's Ark for plants.

It is a highly topical issue less than a month before an international meeting in Brazil to assess just how badly the world is doing in defending its biological diversity.

The bank allows scientists from around the world to study plants in detail never before possible and to take the knowledge back to their communities so they can help them adapt to climate change or restock barren areas.

(China Daily 02/23/2006 page7)