What is solute potential and presasure potential and how they affect the water potential?

The magnitude of the lowering the concentration of waterdue to dissolution of a solute is called solute potential or Ψ_s and itis always negative. If some solute is dissolved in pure water, the solution has fewer free water and the concentration of water decreases, reducing its water potential. Hence, all solutions have a lower water potential than pure water. The more the solute molecules, the lower (more negative) is the Ψ_s. If a pressure greater than atmospheric pressure is applied to pure water or a solution, its water potential increases and it is called as pressure potential and denoted by Ψ_P.