摘要
As China accommodates the biggest population in the world, the development of agriculture, particularly the production of grain and food, has been considered to be a primary important issue of the country. The central government of China has long placed the first priority to the development of agriculture in the Nation’s economy, and this policy will be carded out persistently. Quite naturally, the "grain problem" has not only become a focus of the country, but also attracted the attention of the inter-
