British agriculture must make profound changes, including a total ban on genetic engineering, says a report by two leading environmental campaigns.

The report, from Greenpeace and the Soil Association, says current government agricultural policy "embraces irresponsible short-term priorities and fails to respond to public needs".

It urges an end to modern "industrial" farming and in particular recommends:

• a ban on genetic engineering in food and farming
• a phase-out of artificial chemical inputs
• a long-term shift of all farming to organic methods.

The call comes as a separate report shows that nearly 60% of rural land managers believe land would lose value if used for genetically modified (GM) crops.

The BBC's Robert Pigott: A lack of knowledge has often led to apprehension

The report, from the Royal Institution of Chartered Surveyors, claims only one in 10 of its land managers would advise farmers and land owners to grow GM crops.

More than 40% believe that the growth of GM crops would also reduce the value of neighbouring land, according to the report, which calls for more research to be carried out.

But SCIMAC, the Supply Chain Initiative for Modified Agricultural Crops, which represents GM companies, says that GM crops have been grown widely in the USA and Canada for three years, without a fall in land prices.

Mass vegetarianism

The report from Greenpeace and the Soil Association has been met with reservations by Dr John McDonagh, an agronomist and soil fertility expert at the University of East Anglia.

The BBC's Margaret Gilmore: Most land managers believe GM crops would devalue land

"It is unrealistic to think of phasing out chemical inputs without a dramatic change in our way of life", he says. "Beef and pork production at the levels we require are impossible without large quantities of chemicals.

"There would have to be a mass move to vegetarianism. And making all farming organic would cut down choice, leave far more land marginal, and drive up imports."

Nonetheless, he does concede that, "perhaps we have to go some way in that direction."

Our appetite for meat is hard to satisfy

Many opponents of GM crops want a moratorium on their use, to allow for what they see as proper testing.

But the groups behind the report want the technology completely banned from agriculture.

The Soil Association was instrumental in persuading Wiltshire farmer Captain Fred Barker to destroy a GM crop of oilseed rape on his land.

The report says that "we pay for the consequences of industrialised farming practices three times over - as consumers of increasingly contaminated food and water, as taxpayers, and as potential victims of food-related illnesses."

Chemical traces

Health effects detailed in the report include the discovery in 1996 of traces of the insecticide lindane in more than 40% of UK milk, cheese and butter samples.

It also says a supermarket apple may have been treated 40 times with any of 100 chemicals, and that the risk of eating an apple with very high residue levels is one in 1,000.

On economic impacts, the report says organic farming creates jobs, because it relies on management rather than chemicals.

And it says consumers pay £7.57 through their water bills to clean up each kilogram of active pesticide that a farmer uses.

The report, entitled "The True Cost of Food", says intensive agriculture also entails "massive destruction of natural habitats and consequent loss of wildlife".