Top users of nitrogen-based fertilizer by country

The main micronutrients are molybdenum, zinc, and copper. These elements are provided as water-soluble salts. Iron presents special problems because it converts to insoluble (bio-unavailable) compounds at moderate soil pH and phosphate concentrations. For this reason, iron is often administered as a chelate complex, e.g., the EDTA derivative. The micronutrient needs depend on the plant. For example, sugar beets appear to require boron, and legumes require cobalt.

Reference 1: Total N use (Mt pa) and Amt. used for feed/pasture (Mt pa).

Reference 2: China, India, U.S., France, Germany, Brazil, Canada, Turkey, UK, Mexico, Spain and Argentina.

Source: http://en.wikipedia.org/wiki/Fertilizer