Hydroponics and Aeroponics
1. Hydroponics or Soilless culture: Von Sachs developed a method of growing plants in nutrient solution. The commonly used nutrient solutions are Knop solution (1865) and Arnon and Hoagland Solution (1940). Later the term Hydroponics was coined by Goerick (1940) and he also introduced commercial techniques for hydroponics.
In hydroponics roots are immersed in the solution containing nutrients and air is supplied with help of tube (Figure 12.3).
2. Aeroponics: This technique was developed by Soifer Hillel and David Durger. It is a system where roots are suspended in air and nutrients are sprayed over the roots by a motor driven rotor (Figure 12.4).