Question

Which of the following used in tissue culture is free from viruses?

• A. A plant
• B. Root of a plant
• C. Shoot of a plant
• D. Shoot apex

Answer 1

The correct option is D Shoot apex

Apical meristems in the infected plants are generally either free or carry a very low concentration of the viruses. The various reasons attributed to the escape of the meristems by virus invasion are:

a) Viruses move readily in a plant body through the vascular system which in meristems is absent,

b) A high metabolite activity in the actively dividing meristematic cells does not allow virus replication and

c) A high endogenous auxin level in shoot apices may inhibit virus multiplication.

Therefore, the main objective of shoot-tip and meristem –tip culture is the production of disease-free plants through micropropagation.

Therefore, the correct answer is option D.