Water is the most abundant constituent of all physiologically active plant cells, ranging between 55-85% of the water content of leaves. Water is an important parameter for plant growth or yield representing a complex hydrodynamic system, which involves absorption of water from the soil, water translocation throughout the plant and, its loss to the environment - transpiration. The capacity of plants to meet the demand and thus to avoid water deficit depends on this hydrodynamic system. Since water relations of a plant are closely related and affected by the environment we need to closely monitor at least:
- soil properties in particular the water content which determines the water that is potentially available for transpiration,
- air humidity and temperature around the leaves as the two major factors which affect the evaporation of water into the air.
Nobel PS (2005) Physicochemical and environmental plant physiology. Elsevier Academic Press, Amsterdam.