Question

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

Answer 1

Guttation is a process seen in certain plants like tomato, strawberry, etc, and is sometimes confused with dewdrops. It occurs at night and it occurs to maintain water balance in the plant body.

complete step by step answer:
Guttation is the loss of water in the liquid form from certain parts of plants, usually from tips and/ or margins of leaves. In this process, the water exudes from a group of leaf cells called the hydathodes. Hydathodes are openings or pores on the leaf epidermis, which are grouped together as several thin-walled parenchyma cells.
Guttation occurs during the night or early morning when there are high atmospheric humidity and less or no transpiration occurs as most plants have their stomata closed. The process of guttation depends upon root pressure. The development of root pressure occurs as the water potential of roots is lower than the soil which leads to positive hydrostatic pressure in xylem sap present throughout the plant. Since the water- conducting xylem elements in a vascular bundle terminate at the hydathode, xylem sap is forced to flow through these hydathodes forming water droplets on the surface.

Additional Information: Sometimes the guttation fluid may contain a variety of organic and inorganic compounds like sugars and minerals like potassium. Sometimes it can be indicative of certain events like fertilizer burns in case of which the guttation fluid has high levels of nitrogen.

Note:
- Guttation should not be confused with dew formation. - Guttation is a physiological process that occurs in certain plants and occurs through hydathodes present on leaf tips and leaf margins. - Dewdrops are formed as a result of condensation of the atmospheric moisture on the cold surface of the leaves at night or in the early morning. - Unlike guttation, dewdrops are generally formed on the leaf body and not on the margins, however, they may trickle down to the leaf tips and create confusion.