Blueberry root system has no root hair and its absorption capacity is small. The roots of blueberry are thin and fibrous, and the diameter of the fine roots before branching is 50-75 μ m. Almost all the fine roots of blueberry are parasitic by endophytic mycorrhizal fungi, thus overcoming the difficulty of water and nutrient absorption caused by blueberry roots without root hair. Studies have proved that the parasitism of mycorrhizal fungi is beneficial to the growth of blueberries.