Development History 
   In Roman times, farmers found a large field legume planting grain crops in the former, its production has increased, therefore, it is noted that bacteria can increase agricultural soils rich in nutrients. Until the 19th century, Germany's alfalfa growers and some US soybean growers, who use soil alfalfa field or soybean fields, farmland transferred to the new inoculation, so that crop yields can be improved. In 1838, the French agricultural chemist Dobson High (J.B.Boussingault) found legumes can fix nitrogen. And it established the first agricultural experiment station in 1843, the rotation system in a variety of crop yields and components for a more accurate analysis.
  1886--1888 German scientist H.Hellriegal in sand culture proves that only the formation of Rhizobium legumes to fix atmospheric nitrogen. In 1888 the Dutch scholar Bayeux Link (M.W.Beijerinck) isolated rhizobia, which is a breakthrough in terms of microbial fertilizer. It is now clear that the role of rhizobia. They found that these bacteria, prompting the first American company produced and sold Nate Er soil bacterial inoculants in 1898. Since then, there is a lot of bacteria in the soil preparation and crop seed dressing and coating.
  1920s, there are some new soil and microbial agents for field crops, but less than ideal. 1940s, the US Department of Agriculture issued a permit biological pesticides, has been more than 20 different microbial products used for this purpose.
  In 1937, the Soviet microbiologist Kela Xi Kafelnikov and densely developed Sousse gold "fixing bacteria." Thus creating a precedent bacterial fertilizers, for various reasons, this has to stop all microbial fertilizer mass production. 1940, Asia has been developed with cyanobacteria (algae) was used in the main paddy biological fertilizer. Now it still plays a huge role in the ongoing agriculture.
    Regardless of how the history of biological fertilizer, microbial agents still continue to move forward. Since the 1980s, people with great energy and attention to the environment and bio-fertilizer for crops, which is the reason these products can solve some problems, especially pollution and eliminate pollution of the environment. Therefore, to develop a fertilizer having both functions, but also has the ability to eliminate environmental pollution, it is very difficult. The difficulty lies in: (1) A microorganism having to provide plant nutrition functions (such as nitrogen fixation genes, etc.), but does not have the ability to break down pollution (ie, decomposition of substances genes). Gene transfer is very difficult to implement, but also a huge investment; (2) many types of soil pollution-free, now has more than 105 kinds of substances to the environment caused by pollution. These pollutants and chemical composition is different, it is not possible to use 105 kinds of microbes mixed together to make preparations. Gene transfer is more difficult to achieve; (3) In addition to the principles of bio-pesticides and bio-herbicides, etc. and species varies greatly as a bacterium one purpose in principle. So only made a single bacterium. And play a role in a longer time; (4) the agents of biological fertilizer not typical of some microorganism, when its agents into the soil made it difficult to survive, and usually only before using for 3 months shelf life.