About 98% of water absorbed by plants on land
is evaporated from the aerial parts; through transpi-
ration. Due to this the plant has to face several prob-
lems. So the rate of transpiration must to reduced.
For this certain substances are used to reduce the
rate of transpiration. These are known as antitran-
spirants. eg : colourless plastics; silicone oils; phenyl
mercuric acetate