The United Nations and the Organisation for Economic Co-operation and Development backed genetically modified crops as a weapon in the fight to curb hunger, as they warned of a slowdown in growth in agricultural production.

Annual expansion in farm output is, after growing for "several decades" at some 2%, to slow to 1.7% over the next decade, thanks to "growing restraints" on factors such as fertilizer, water and land.

"Growing resource constraints, environmental pressures and higher costs for some inputs are expected to inhibit supply response in virtually all regions," the UN's Food and Agriculture Organisation and the OECD said in a joint report.

Growth through bringing fresh farmland under crops is "limited", with total arable area expected to expand by "only" 69m hectares, equivalent to less than 5% - even by 2050.

The loss in developed nations of 38m hectares to the likes of urbanisation will offset in part expansion of 107m hectares in developing nations.

 'Sustainable' future

The ability of agriculture to meet the needs of a world population expected to grow by 680m by 2021, and relying increasingly on biofuels, means that "the key issue facing global agriculture is how to increase productivity in a more sustainable way".

Sustainable agriculture means not just using fertilizers, agrichemicals and water in more efficient ways, besides acting to limit soil erosion to protect farmland, but "harnessing plant breeding and biotechnology", the briefing said.

"Achieving sustainable agricultural productivity growth will largely depend on farmers' ability to adopt the latest technologies," of which genetically modified seed is "perhaps the most rapidly-adopted crop technology in agriculture today".

Biotech benefits 

Biotech seed can, in helping growers cut use of other inputs and increasing yields and the predictability of crops, "improve farmers' output and incomes".

Seeds are also being developed that "cannot only survive in extreme climates, but can maintain and even increase crop yields" in these areas, many of which are in emerging countries.

Furthermore, the next generation of genetically modified crops "is expected to provide direct consumer benefits", such as varieties enhanced for extra vitamin content.

Indeed, the organisations urged action to ensure patents for seed groups, saying "agricultural advances are no different from other inventions, and should be afforded the same intellectual property protections".

They also flagged biotech firms' reinvestment of a "significant proportion" of their sales back into research.

Controversial technology 

The comments come amid continued controversy in some regions over genetically modified crops - notably in Europe, where France, where the OECD is based, has proved particularly vehement in its condemnation of the technology.

Protesters have cautioned that the technology may cause long-term harm, of which proponents are not yet aware.

While many anti-GM protests, such as those at last month's International Bio Convention in Boston, US, have proved peaceful, others, including an attack on UK research into biotech wheat, have crossed the line into criminal behaviour.