How can tissue culture be used to get back the healthy plants from diseased plants?
Meristem can be removed and if grown in vitro virus-free plants can be obtained
By removing the roots and growing them in vitro to obtain disease-free plants
By exposing the plants to antibiotics in the nutrient medium
By exposing the plants to radiation to kill the virus
Explanation of the correct option
Tissue culture can be used to recover healthy plants from diseased plants by removing the meristem and growing it in vitro to obtain virus-free plants. Although the plant may be infected with a virus, the meristem is often free of the virus. By growing the meristem in a nutrient-rich medium under sterile conditions, it is possible to obtain virus-free plants. This technique has been successfully used to obtain virus-free plants of banana, sugarcane, potato, and other crops. Hence option 1 is the correct answer.
Explanation of the incorrect options :
Option 2 is incorrect because by removing the roots and growing them in vitro to obtain disease-free plants: This statement is incorrect as removing the roots and growing them in vitro cannot guarantee the removal of the disease from the plant. The roots may contain the same virus or disease as the rest of the plant.
Option 3 is incorrect because by exposing the plants to antibiotics in the nutrient medium: Antibiotics are used to kill bacteria, not viruses. Therefore, exposing the plants to antibiotics will not remove the virus.
Option 4 is incorrect because exposing the plants to radiation to kill the virus: Although radiation can be used to kill viruses, it is not a practical method for removing viruses from plants. Radiation can damage plant cells and may cause mutations, making it an unsuitable method for virus removal.