Transpiration - What and Why?

Transpiration - What and Why? transpiration Transpiration is caused by the evaporation of water at the leaf–atmosphere interface; it creates negative pressure equivalent to –2 MPa at the leaf transpiration As we know, transpiration takes place in tiny pores in the epidermis of leaves called stomata Water evaporates in the leaf cells forming water vapor The air

transpiration The role of the stomata · Transpiration is mainly controlled by the pairs of guard cells that surround stomata · Guard cells open the stomata

transpiration When stomata are open, transpiration rates increase; when they are closed, transpiration rates decrease • More stomata will provide more pores HORMONAL REGULATION OF TRANSPIRATION When plants are drought stressed, the plant hormone ABA accumulates in the shoot, where it both inhibits stomatal opening