China has officially approved imports of a genetically modified Bayer CropScience soybean variety after seven years of review, the company said on Friday, raising expectations that approval notices will come soon for other grains.

Bayer received an import certificate from China for its LL55 Liberty Link soybean, which is engineered to help farmers control weeds. This new trait of Liberty Link soybean is a sister one to Liberty Link soybeans that have been planted, harvested and exported around the world, which is officially recognized as LL27.  A full commercial launch of the new LL55 varieties will occur in 2015, a spokesman said.

A company spokesman noted the difference between the Liberty Link numbers is a small genetic difference in position of one or more genes, but the difference will allow the potential for new stacked trait varieties. In general, the new L55 beans will provide similar performance to current high-yielding Liberty Link varieties. 

The slowdown in Beijing's regulatory process has been due to growing consumer sentiment against GMO food in China and concerns amongst some government officials about excessive dependence on U.S. food supplies. The delay cast doubt over the future of seed companies' heavy investments in research of GMO seeds, which can take up to 10 years and $150 million to develop.

U.S. Agriculture Secretary Tom Vilsack on Wednesday said China had approved imports of U.S.-grown Agrisure Viptera corn, developed by Swiss-based Syngenta, as well as shipments of biotech soybeans developed by Bayer and DuPont Pioneer. However, the companies had not received official notices from China.

Syngenta said it had not yet received official notification for Viptera, known as MIR 162. DuPont did not immediately respond to an e-mail.

Bayer withheld the LL55 soybean seed from the market as it waited for approval from China, the world's top importer of the oilseed. The company reported that China was the last approval for which the company had been waiting for years.

Beijing has been taking longer than in the past to approve new GMO crops. Chinese ports in November 2013 began rejecting U.S. corn imports saying they were tainted with MIR 162, approved for planting in the United States but not for import by China.

Commodity traders Cargill Inc and Archer Daniels Midland Co, along with dozens of farmers, have sued Syngenta over MIR 162, claiming hundreds of millions of dollars in damages because of the rejections.

China is a key market for the $12 billion U.S. agricultural seeds business and for global grain traders, and accounted for nearly 60 percent of U.S. soybean exports and 12 percent of corn exports two years ago. Nearly 90 percent of corn in the United States is genetically engineered, according to the U.S. Department of Agriculture, as farmers embrace technology that helps kill weeds and fight pests.