If excess fertilizer is placed around the root of a tomato plant, the leaves of the plant will shrivel and turn brown. explain this phenomenon in terms of tonicity.

It is best to mix the fertilizer with the soil so it will be distributed evenly. Placing fertilizer near the root directly is dangerous as the fertilizer concentration will be too high. If the concentration of fertilizer too high, the osmotic pressure or tonicity of the solution will be high. It will attract water of nearby cell and make it shrink. The plant cell will continuously lose water, shrink and then shrivel because of this.