For ascent of sap capillary force theory was first proposed by

For the ascent of sap, capillary force theory was first proposed by Christian Wolf.
The ascent of sap in the xylem tissue of plants is the upward movement of water and minerals from the root to the aerial parts of the plant.
The Capillarity of the vessels and the normal atmospheric pressure are responsible for the ascent of sap. The vessel capillaries exert some force that helps to raise the water to a certain height of the stem.