What is guttation?
1 Answer
Guttation is the exudation of drops of xylem sap on the tips or edges of leaves of some vascular plants, such as grasses.
Explanation:
As the stomata close at night, transpiration does not occur. Due to high soil moisture levels, water enters the plant roots. The water accumulates in the plant, creating a sligh root pressure. This root pressure forces some water to exude through special leaf tip structures, hydathodes or water glands forming drops.
It is the root pressure that provides the impetus for this flow, rather than transpirational pull. Guttation is most noticeable when transpiration is suppressed and the relative humidity is high e.g. during night.
Guttation fluid may contain a variety of organic and inorganic compounds mainly sugars and potassium. On drying, a white crust remains on the leaf surface.
