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Question
What is the major advantage of producing plants by micropropagation?
Solution
Micropropagation - This method of producing thousands of plants by tissue culture is called micropropagation. In this, each plant is genetically identical to the original plant from which they are prepared. These are called somaclones. Most of the important food plants like tomato, banana, apple etc. have been produced on a commercial scale by this method.
This method can prepare thousands of plants in a very short period. Another important application of this method is recovering healthy plants from diseased plants. Although the plant is infected by the virus, the meristem (apical and axillary) remains free of the virus. Hence, the meristem is separated and grown in in vitro culture so that virus-free plants can be prepared. Scientists have succeeded in culturing meristems of banana, sugarcane, potato, etc.
Scientists have even isolated single cells from plants and, after digesting their cell walls, have been able to isolate naked protoplasts (surrounded by plasma membranes). Isolated protoplasts from two different varieties of plants - each having a desirable character – can be fused to get hybrid protoplasts, which can be further grown to form a new plant. These hybrids are called somatic hybrids while the process is called somatic hybridisation.
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