Fertilizers was dissolved by moisture in soil,become into the nutrient, root through the flow and diffusion two ways to absorb nutrients.
Flow is through the crop water transpiration, with soil moisture and nutrients to the root of the surface, moved by the roots.
Diffusion is the root crops with nearby soil nutrient absorption, the rhizosphere soil nutrient quantity relatively lower part, cause other nutrient concentration in the soil, other parts to the root surface nutrient, migration, root absorbed.
Flow and diffusion is the main way root absorb nutrients. Also has a few fertilizer nutrients, with its roots when direct contact, directly by ion exchange, root absorbed, not through the soil solution, this way, through intercepting called the nutrient absorption intercepted.
For all the crop root, can be divided into four regions, beginning from the root upward, differentiation area, elongation area, mature area,full mature area. Mature area form many hair, it is the most active area for absorbing nutrition and moisture.At this area, fertilizer should be absorbed to crops.
From the root absorbed the characteristics, fertilizer must combined irrigation, must be able to state, dissolve fertilizer on flow or diffusion modes to be absorbed by roots,increasing the contact area between fertilizer and roots, to improve the effectiveness of fertilizer effect.