Plants and any from of living organisms cannot live without water, since water is
the most important constituent about 80 to 90% of most plant cell.
Role of water in crop and crop production can be grouped as
A) Physiological importance
• The plant system itself contains about 90% of water
• Amount of water varies in different parts of plant as follows
• Apical portion of root and shoot >90%
• Stem, leaves and fruits – 70 – 90%
• Woods – 50 – 60%
• Matured parts – 15 – 20%
• Freshly harvested grains – 15 – 20%
• It acts as base material for all metabolic activities. All metabolic or biochemical
reactions in plant system need water.
• It plays an important role in respiration and transpiration
• It plays an important role in photosynthesis
• It activates germination and plays in important role in plant metabolism for
vegetative and reproductive growth
• It serves as a solvent in soil for plant nutrients
• It also acts as a carrier of plant nutrients from soil to plant system
• It maintains plant temperature through transpiration
• It helps to keep the plant erect by maintaining plant’s turgidity
• It helps to transport metabolites from source to sink
B) Ecological Importance
• It helps to maintain soil temperature
• It helps to maintain salt balance
• It reduces salinity and alkalinity
• It influences weed growth
• It influences atmospheric weather
• It helps the beneficial microbes
• It influences the pest and diseases
• It supports human and animal life
• It helps for land preparation like ploughing, puddling, etc.,
• It helps to increase the efficiency of cultural operations like weeding, fertilizer
application etc., by providing optimum condition.
The multifarious uses of good quality water for the purpose of irrigation,
industrial purposes, power generation, livestock use, domestic use for urban and rural
development, are increasing the demand for water. Due to increasing cost of irrigation
projects and limited supply of good quality water, it becomes high valuable commodity
and hence it is stated as Liquid Gold. Further, historical evidences indicate that all
civilization established on water base due to proper management and disappear due to
improper management of the same water base. All the superior varieties, organic manure,
inorganic fertilizer, efficient labour saving implements, better pest and disease
management techniques can be implemented only when sufficient water is applied to the
crop. The diversified value of water can be quoted as follows:
- Water as a source of sustenance
- Water as an instrument of agriculture
- Water as a community good
- Water as mean of transportation
- Water as an industrial commodity
- Water as a clean and pure resource
- Water as a beauty
- Water as a destructive force to be controlled
- Water as a fuel for urban development
- Water as place for recreation and wild life habitat
