Chinese farmers using nuclear tech to boost crop yield

Some of the Chinese farmers have sown the seeds irradiated by Heilongjiang Academy of Agricultural Sciences (HAAS) and are monitoring the growth of the crop.

"I just want to try it. I hope nuclear technology can help me to raise either the output or quality of crops," Li Weiguo a farmer in Shuqing Village near Shuangcheng City who had sown the irradiated seeds soybean and corn this summer, expecting new varieties with higher yields.

It is the first time the 33-year-old farmer in China's Heilongjiang Province has had seeds irradiated with the help of agricultural experts.

The irradiation process involves exposing seeds to low doses of gamma rays from cobalt-60, a radioisotope of cobalt, which causes changes in the seed's genetic makeup, said Xu Dechun, vice director of the institute.

It usually took experts about five years to screen out seeds for new varieties with stable genetic characteristics, Xu told Xinhua newsagency.

Compared with the widely used cross-breeding method, which largely depended on opportunity and usually took about eight years to get a stable variety, seed irradiation intervention was far more effective in bringing out the desired characteristics of a certain crop, he said.

Xu's team has developed 28 new soybean breeds, almost 20 wheat varieties and a dozen corn varieties.

More than seven million hectares of farmland in Heilongjiang have grown such crops, which raised yields by more than 50 million kilogrammes.

China is the world's largest grain producer and consumer. The central and local governments have been supporting the application of nuclear technologies in agricultural development.

Huge investments have been made in research programmes across the country and almost every province has established atomic energy institutes, Liang Qu, director of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, said at the third Global Forum of Leaders for Agricultural Science and Technology.

The FAO and IAEA had continuously promoted the application of nuclear technologies in agriculture since 1950, he said. So far, more than 3,000 new varieties have entered mass production worldwide for commercial purposes. In addition to developing new varieties, irradiation is also used to retard spoilage and increase the shelf life of food.

In China's eastern province of Shandong, exposing garlic to low doses of gamma rays from cobalt-60 could postpone sprouting, which allowed garlic to be preserved in normal temperatures for longer, Xu said.

So far, China has approved the application of the technique for more than 30 types of food, including meet, dried vegetables, shrimp and fruits.

Many countries like the United States and Japan had recognised food irradiation, as the method did not make the food radioactive, and did not change the food any more than canning or freezing, he said.

The US Food and Drug Administration has approved the use of irradiation for fruit, vegetables, pork, poultry, red meat and spices. Food irradiation kills bacteria, insects and parasites that can cause food-borne diseases, such as salmonella, trichinosis and cholera.

According to the US Department of Agriculture, food-borne illnesses affect more than 76 million Americans and kill more than 5,000 each year. The World Health Organisation believed the technology was absolutely safe to people and food after a 10-year survey, Liang said and no problems concerning radiation-induced mutation had been found.
Unlike genetically-modified crops, which could introduce new genetic codes from other plants or species into their genetic makeup to create new characteristics, nuclear radiation-induced mutation simply accelerated the process of spontaneous genetic changes, he said.

In agriculture, radiation could help kill insect pests, develop more disease-resistant crops, improve the nutritional value of some crops or their baking or melting qualities or reduce their cooking time, said Trevor Nicholls, chief executive officer of CAB International Head Office in the United Kingdom.

Chinese specialists were still researching many of the functions of irradiation, Xu said. His staff previously launched an irradiation program to kill the sperm of a certain pest insect in a move to curb insect disease.

"The project failed and we are planning to resume the research and experiments once the authorities approve it," he said. He said the future research would focus on combining seed irradiation with trans-gene technology, cross-breeding and chemical breeding means to develop disease-resistant and natural disaster tolerant varieties.

It has been predicted that the world's population will exceed nine billion by 2050, posing an even greater challenge to food security.

Along with other means, nuclear technology was expected to help ease the gap between food supply and demand by increasing agricultural productivity and food quality, Tang Huajun, vice president of the Chinese Academy of Agricultural Sciences said.