"In the next 20 to 50 years we have to reverse our dependency on fossil fuels," said Alison Smith of Britain's John Innes plant research centre. "We must breed for sustainability."
At a news conference on Monday, she complained that in the past there had been a lack of coherent thinking, but that was now changing in the face of the looming crisis.
Ian Crute, director of the Rothamsted plant-breeding centre in Hertfordshire, said it was not a matter of switching wholesale out of growing crops for food but of correcting the balance.
"We have an opportunity here...to substitute our dependency on fossil fuels," he added at the introduction of a report by private scientists on non-food crops entitled "Growing the Future."
Not only was oil running out, but the world's population was predicted to grow sharply over the next half century and had to be fed. This would put huge strains on the world's economy.
"We have to get more productivity out of less land," he said.
The report noted that plants could produce plastics, fuels, oils, medicinal drugs, insulators, fibres and fabrics, many of which are currently made from crude oil.
Smith said it was not just a matter of genetic manipulation of existing crops - although that too had a place - but of making better use of plants currently grown for food.
"We have to get more productivity out of less land"
Rothamsted plant breeding centre, Hertfordshire, UK
Plants could also be bred for specific uses such as special types of oils or fibres.
They could in effect be used as "green factories" to produce whatever mankind needed in the future, she said.
Farmer and businessman Clifford Spencer - who grows crops for industrial uses - said some research suggested that between one quarter and one third of the farmland in Britain could switch to such uses.
He said that while their arguments were not new, the science to make it happen was, and businesses around the world were waking up to the urgency and the possibilities.