Which part of the plant is best suited for making virus-free plants and why?
The meristem (apical and axillary) is best suited for making virus-free plants.
Even if the plant is infected with a virus, the meristem remains free of virus. Hence, one can remove the meristem and grow it in vitro to obtain virus-free healthy plants. This is an important application of tissue culture for the recovery of healthy plants from diseased plants.
Scientists have succeeded in culturing meristems of banana, sugarcane, potato, and other crops using this technique.
Explanation
According to the textbook, the meristem is the ideal plant part for obtaining virus-free plants because it remains free of viruses even when the rest of the plant is infected. This property allows scientists to excise the meristem and culture it in vitro to regenerate healthy, virus-free plants. This application of tissue culture has been successfully demonstrated in crops like banana, sugarcane, and potato.
Solution Steps
Step 1: Identify the meristem (apical and axillary) as the virus-free part of an infected plant
Step 2: Explain that meristem can be grown in vitro to produce virus-free plants
Step 3: Mention examples of successful meristem culture in banana, sugarcane, potato etc.