A technique to produce high-yield rice genetically modified (GM) using a gene from maize is still under academic discussion and not ready for practical application, an expert said on Friday.

Deng Qiyun, chief scientist of China's hybrid rice national key laboratory and a student of Yuan Longping, known as "the father of hybrid rice," told Xinhua there is still a long way to go before the technique could be applied to actual production.

Yuan Longping said in an earlier interview that he was trying to improve rice's efficiency in photosynthesis and thus raise yields by integrating a C4 gene from maize into rice.

The report caused a stir among some members of the public who are concerned over the safety of GM food.

"C4 plants such as maize and sugarcane are more efficient in photosynthesis than C3 plants including rice, wheat and soybean," Deng said, adding there could be an increase of at least 30 percent in output if the technique succeeds.

But Deng said there is still a lot of room to raise the yield of rice using conventional techniques. "A yield of 1,200 kg per mu (0.0667 hectares) is scientifically feasible," Deng said.