National legislators from Heilongjiang province, which is China's principal producer of non-genetically-modified soybeans, are calling for a law to set up a special zone where the planting and processing of GM plants is prohibited.

Deputies to the country's top legislature hope such a law would preserve ecological diversity, benefit farmers who plant non-GM soybeans and avoid "possible contamination" of the soybean crop by GM plants.

The size of the proposed special zone would restore the province's soybean growing acreage to its 2010 level of 4.3 million hectares, said national lawmaker Tan Zhijuan.