Question

What happens if plant cell is kept in highly concentrated salt solution

Answer 1

Plasmolysis is the shrinking of the cytoplasm of a plant cell in response to diffusion of water out of the cell and into a high salt concentration solution. During plasmolysis, the cell membrane pulls away from the cell wall. This does not happening low salt concentration because of the rigid cell wall.

Answer 2

If you keep a plant cell in highly conc. salt solution, the solution being at a higher concentration than the cell sap causes exosmosis  to occur thus the water is drawn from inside the cell and the cell shrinks in size and becomes flaccid.