Question

explain about root pressure?​

Answer 1

Root pressure is the transverse osmotic pressure within the cells of a root system that causes sap to rise through a plant stem to the leaves. Root pressure occurs in the xylem of some vascular plants when the soil moisture level is high either at night or when transpiration is low during the day. 

Answer 2

the root pressure is simply the pressure in the root of a plant. this pressure is also defined as osmotic pressure.