The cells which have the ability to divide and result in the growth of the plant are called meristem. The meristem is free from the virus even though the plant is infected with a virus. This is because the division of meristematic cells is faster than the rate of replication of the virus, less differentiation of meristematic cells, etc. Thus to develop a virus-free plant, culturing the meristem would be a suitable option. Cultivation of plants without soil and just by the use of nutrient-rich water is called hydroponics. Transfer of pollen grains from the anther to the stigma of the same flower or different flowers of the same plant is called self-pollination. A hybridisation technique in which the desired pollen grains are used for pollination by artificial means is called artificial hybridisation.