What is the process by which water enters young roots or mycorrhizal roots?

The process by which water enters young roots or mycorrhizal roots is primarily osmosis. Osmosis is the movement of water molecules through a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration. In the case of roots, the surrounding soil typically has a lower concentration of solutes compared to the interior of the root cells, allowing water to move into the roots through osmosis.

This mechanism is crucial for water uptake, especially in plants that have young roots or those associated with mycorrhizal fungi. Mycorrhizal associations enhance the plant's ability to absorb water and nutrients through a vast network of fungal hyphae that increase surface area for absorption. Thus, osmosis plays a vital role in sustaining the hydration and overall health of plants as they establish their root systems.