Mineral Nutrition Test - 8

Cultivation of plants by placing the roots in the nutrient solution (in complete absence of soil) is called hydroponics. It is necessary to aerate the solution to provide roots with adequate oxygen supply. The result obtained from soil-less culture may then be used to determine deficiencies under field conditions.

The given experimental set-up shows nutrient solution culture. In this typical solution culture technique, nutrient solution is placed in superior glass jars or polythene bottles covered with black paper (to prevent growth of algae and reaction of roots to sunlight). The jars contain split covers or corks with holes for suspending seedling, a funnel for adding solution and a bent tube for aeration, as shown in the given figure. Regular aeration is required for proper growth and activities of roots.

Hydroponics or soilless culture helps to know:
- The essentiality of mineral elements.
- The deficiency symptoms developed due to non-availability of particular nutrient.
- Toxicity to plant when element is present in excess.
- Possible interaction among different elements present in plants.
- The role of essential element in the metabolism of plant.

The technique of growing plants in a nutrient solution is known as hydroponics. Hydroponics is useful in areas having thin, infertile and dry soils. Hydroponics can regulate pH optimum for a particular crop, control soil borne pathogens, avoid problems of weeding and obtain consistently better yield. Out of season vegetables (e.g., tomato, seedles cucumber, letture) and flowers can be obtained through hydropnic.

In 1860 Julius von Sachs, Professor of Botany at the University of Wurzburg published the first standard formula for a nutrient solution that could be dissolved in water and in which plants could be successfully grown. The technique was termed “nutriculture”.  Now it is called Hydroponics.