Soaring food prices and global grain shortages are bringing new pressures on governments, food companies and consumers to relax their longstanding resistance to genetically engineered crops.

With food riots in some countries focusing attention on how the world will feed itself, biotechnology proponents see their chance. They argue that while genetic engineering might have been deemed unnecessary when food was abundant, it will be essential for helping the world cope with the demand for food and biofuels in the decades ahead.

Through gene splicing, the modified crops now grown–mainly canola, corn, cotton and soybeans–typically contain bacterial genes that help the plants resist insects or tolerate a herbicide sprayed to kill weeds while leaving the crop unscathed. Biotechnology companies are also working on crops that might need less water or fertilizer, which could have a bigger impact on improving yield.