Question

What is guttation? Explain with the help of diagram of the vertical section of hydathode present on apical part of tomato or primula leaf.

Answer 1

Guttation is the loss of water in the liquid state from uninjured parts of plants, usually from tips and margins of leaves. In this, water exudes from the group of leaf cells called hydathodes.

A hydathode is an opening or pores in the leaf epidermis, around, which are grouped as several thin-walled parenchyma cells. It occurs during the night or early morning when there is high atmospheric humidity and transpiration is less. Guttation depends on the root pressure. The development of root pressure in a plant leads to positive hydrostatic pressure in xylem sap throughout the plant. Because of water-conducting xylem elements is a vascular bundle terminate in a hydathode, xylem sap is forced to flow through the hydathodes.