Transpiration and guttation are sometimes understood similar to each other. Both of these are involved in losing the water from the plant. There is a very simple difference in between them. The key difference lies in the way the plant loses water. In case of transpiration the water is released in the form of water vapors from the aerial parts of the plant. While in case of guttation, the water is released in liquid form from the margins of the leaves. So the main difference is that water is released in vapor form in transpiration and liquid form in guttation.
Leaf stomata, cork bark lenticels and the cuticle covering the epidermis of herbaceous plants represent the natural escape routes of transpired water (which also helps to avoid overheating of the leaf surface due to solar radiation ). Two of the processes to release this water are which we will be discussing.
Now we will go through both of these processes one by one.
Plants need water for living. Plants absorb water through roots from the soil. When they have excessive water, it can be dangerous for the plant. So the plant needs to remove extra water from the body. Through the transpiration process, the water is lost from the aerial parts of the plant. Transpiration needs sunlight and heat to occur. So mostly it occurs during the daytime. Transpiration gives cooling effect to the plants. Considering the place of transpiration, there are three types of it.
The stomatal transpiration is the most common type which occurs through stomata. Another one is the cuticular transpiration that occurs through the cuticle of the leaf. The lenticular transpiration occurs through the lenticels which are present on the stem. So the main function of transpiration is to keep the temperature low. There are some factors that affect the rate of transpiration. These factors include temperature, humidity, light intensity, water and the soil of the area.
Guttation is the loss of water through the aerial parts of the plant in liquid form. In transpiration, the water is lost in water vapors form while in guttation it is lost in liquid form. Guttation mostly occurs at night. It occurs in herbaceous plants which grow in high humidity conditions. Guttation occurs where the moisture in soil is very high. Guttation is an altered process of losing water by plants. When the transpiration doesn’t occur or the transpiration rate is low, guttation helps the plant in losing the excessive water. The root pressure increases which makes the water drops leave the plant through special type of pores on leaves known as Hydathodes.
Main differences between Transpiration and Guttation:
Now we will enlist the key differences among these two processes.
Transpiration loses water in the form of vapors while Guttation loses in liquid form.
Guttation occurs through special pores known as Hydathodes while transpiration occurs through stomata, cuticles and lenticles.
Transpiration and guttation do not occur together. The transpiration occurs during the daytime while the guttation occurs during the night.
The water which is lost through transpiration is pure while the water through the guttation process contains impurities including organic and inorganic substances.
If there is excessive transpiration, it may cause wilting while guttation never causes wilting.
Under stressful conditions, the guttation may stop but the transpiration does not stop in any condition.