Here is how virus free plants are produced, short and simple.
The virused plant is grown in tissue culture at a very warm temp. which causes the plant to out grow the virus (I forget what temp but not 120F ). Then the meristem, the very small, microsopic cells at the tip of the growing point, are excised, grown in tissue culture to a rooted plantlet and grown out into real plants which are them retested to see if they are virus free. Usually several of these meristems are produced in hopes of getting one virus free plant. And that is how heat helps to get rid of plant viruses.
From my distant past as a tissue culture queen.
