The rate of water absorption is decreased due to deficiency of

The rate of water absorption is decreased due to deficiency of Potassium. Potassium is needed for controlling both water uptake and the process of allowing plants to harness energy from the sun.
The deficiency of potassium might have reduced aquaporin activity, consequently suppressing root hydraulic conductance and water supply to the growing stem for diameter expansion and leaf for transpiration, thus it ultimately affects the rate of absorption of water from roots.