Transpiration is the evaporation of water from cell surfaces and its loss through the anatomical structures of the plant (stomata, lenticels and cuticles). The total water loss by transpiration may be very great. The daily water loss of large, well watered tropical tress may run as high as 500 litres. A corn plant may loose 3 to 4 litres of water per day. Whereas a tree sized desert cactus may loose water less than 25 ml per day. In general about 99 per cent of water absorbed by a plant during the growth is lost in transpiration (necessary evil). Water lost by a growing field of corn would be about 8-11 inches of water per acre during the growing season. Transpiration is mostly taking place through the stomata.
Although large quantities of water are absorbed by plant from the soil, only a small amount is utilized. The excess of water is lost from the aerial parts of plants in the form of water vapour and this process is called as transpiration. Nearly >95 per cent of water absorbed by the plants is lost through transpiration and only <5 per cent is utilized by the plant. In general, there are 3 types of transpiration i.e. stomatal, cuticular and lenticular transpirations.



Transpiration proces

Last modified: Monday, 25 June 2012, 8:19 AM