The study of micronutrients began in the early 20s of this century and is only about 60 years old. Micronutrient research is part of plant nutrition research.
The study of trace elements goes beyond the research of soil scientists, agricultural chemists, and physiologists, and also pays great attention to ecologists and experts in environmental science. The production and development of micro-fertilizers is the same as that of nitrogen, phosphorus and potassium fertilizers, but it is only born with the confirmation of micronutrients. The application of micro-fertilizer has become one of the great advances in the field of plant minerals, which has promoted a substantial increase in crop yields.
Micro-fertilizer has practical significance in agricultural production, so it was demonstrated and popularized in agriculture in the 30s. For example, in the Soviet Union, 2,700 tons of boron fertilizer (boron-magnesium fertilizer) were applied in 1937~1939. In the late 40s, the annual application of borax in the United States reached 4148 tons, and the annual use of zinc sulfate reached 3311 tons in the 50s. The annual use of micro-fertilizer in the Soviet Union amounted to 120,000 tons, and in the United States up to 200,000 tons. The production of micro-fertilizers in China has a history of more than 20 years. In 1964, the production of molybdenum fertilizer was first started in Jilin germanium plant, which had a significant effect on soybean yield. Since the 70s, the agricultural department and the relevant units of the Chinese Academy of Sciences have successively discovered that crops have symptoms of zinc, boron, iron, and manganese deficiency, which has attracted the attention of relevant departments. In 1981, the State Economic Commission and others jointly convened the first national conference on trace element fertilizers. In 1983, the total output of micro-fertilizer in China reached more than 20,000 tons, with 24 varieties and an application area of about 40 million mu.
