固氮兰藻作为水稻肥源研究在国外已有四十年的历史,在我国也有二十年的历史了。大量的试验证明,在秧田和大田施放固氮兰藻都可以提高水稻的产量,一般可增产1—2成。1977年,我们在通城县进行固氮兰藻作为双季晚稻肥源的试验,目的是探索固氮兰藻在通城县的生长繁殖规律及验证固氮兰藻对水稻的增产效果。一年中我们共建藻种培养池2亩多,并利用50亩茬口田繁殖藻种5万斤, Nitrogen fixation blue lanna as a source of rice fertilizer in foreign countries have been 40 years of history, in our country also has 20 years of history. A large number of experiments show that the application of nitrogen and nitrogen in the seedling field and field can increase the yield of rice, the general increase of 1 to 2 percent. In 1977, we carried out the experiment of nitrogen fixation of blue photosynthetic blue algae as double crop late rice fertilizer source in Tongcheng County. The purpose was to explore the growth and reproduction regularity of Azadirachtin in Tongcheng County and to verify the effect of nitrogen-fixing of Alnus clavulanicum on rice yield. One year we build algae cultivation pool more than 2 acres, and the use of 50 acres of stubble field spawning species 50000 pounds,