Transpiration is the process in which plants release the water inside it in the form of moisture or water vapor. Parts of plants like stems, small pores on leaves, flowers evaporates the water to the atmosphere. Basically, It is the process in which water is evaporated in the atmosphere from plant leaves and other parts. Some amount of water is consumed by roots and rest is evaporated in the atmosphere.



1. Stomatal: It is the most common process in plants. The loss of water through stomata, It is called stomatal transpiration.

2. Cuticular: It through the gaps or pores in the cuticle is called cuticular transpiration.

3. Lenticular: It is the loss of water from plants as vapor through the lenticels. The lenticels are tiny openings that protrude from the barks in woody stems and twigs as well as in other plant organs.

Factors Effecting Transpiration

  1. Light: Plants transpire more rapidly in the light than in the dark. This is largely because light stimulates the opening of the stomata. Light also speeds up transpiration by warming the leaf.
  2. Humidity: The rate of diffusion of any substance increases as the difference in concentration of the substances in the two regions increases.When the surrounding air is dry, diffusion of water out of the leaf goes on more rapidly.
  3. Temperature: At low temperature, vapour pressure deficit is low and transpiration is low, whereas at high temperature, higher vapour pressure deficit leads to higher rate of It.
  4. Plant Water Status: Higher the availability of water, higher will be the rate of transpiration.
  5. Leaf: Higher the leaf area, higher will be the rate of transpiration. Epidermal hairs on the leaves cause resistance to the movement of water from the leaf surface to the atmosphere. As a result, the loss of water decreases. Such type of vegetation is common in desert area.