Guttation vs Transpiration
Plant absorbs a large amount of water irrespective of their daily requirements. But only 1% of this amount is utilized by plants while 99 % is lost from the aerial parts of the plant. The water is lost either in the form water vapor or rarely in liquid form. Depending on the form of water (liquid or vapor), two terms are used to explain the way of loosing water. They’re transpiration and guttation. These two ways of loosing water can be either good or bad, depending on the surround environmental factors.
What is Guttation?
Guttation is the direct loss of water from the aerial parts of living plants in the form of liquid. It can be seen occurring at night and in the early hours of the morning in herbaceous plants growing under high soil moisture and high humidity conditions. When root pressure is high and transpiration is low, the water in plants is forced out in the form of drops through special pores in tips of leaves called hydathodes.
What is Transpiration?
The loss of water from aerial parts of a living plant in the form of water vapor is known as transpiration. This mainly occurs during the daytime and has a cooling effect on plants. There are three types of transpiration, depending on the place where it takes place; namely, stomatal transpiration, curticular transpiration, and lenticular transpiration.
Stomatal transpiration occurs through the stomata and contributes about 80 to 90 % to the total transpiration. The rest of 10 to 20 % occurs through the other two types. Curticular transpiration takes place through the cuticle of leaves and herbaceous stems. The rate of cuticular transpiration is inversely proportional to the thickness of the cuticle. Lenticular transpiration contributes the lowest amount to the total transpiration of a plant, which is about 0.1 %. Lenticular transpiration takes place through the loosely arranged mass of cells in the bark of stem, known as lenticels.
Transpiration is essential for a plant as it helps in keeping the temperature low, distribution of water throughout the plant, and rapid translocation of minerals and water through the xylem. Transpiration often produces water defects in plants due to the high water loss. The main factors affecting transpiration are light, humidity, air temperature, wind, and available soil water.
What is the difference between Guttation and Transpiration?
• In guttation, water is lost in the form of liquid whereas, in transportation, it is lost in the form of water vapor.
• Transportation occurs during the daytime while guttation occurs mainly during the night time.
• Guttated water contains salts and sugars, whereas transpired water does not.
• Guttation occurs through the hydathodes on leaf tips while transportation takes place mainly through stomata.
• Transpiration has a cooling effect on plants, whereas guttation does not.
• Transpiration is a controlled process, whereas guttation is not.
• Guttation depends on root pressure while transpiration does not.