Relation of Water Content to Functions

If an aquatic plant appearing turgid is removed from water and left in the open, it quickly wilts. The water content of the leaves may change hardly by 3 to 5 per cent but the plant looks functionless. This is also true for young leaves of wheat which have 90-95% water; they wilt if water content drops by 3-4 per cent. However, an older leaf has only 80-85% water but is fully turgid. Thus, water content cannot be the basis of judging the activity of leaves. Therefore, it is necessary to have an expression for plant water status which could be related to plant function. We will discuss this in one of the sections later.