Which of the following are fused in somatic hybridization involving two varieties of plants?

Which technique can be used to develop seedlings from seeds that have remained dormant for a long time?

What is the major advantage of producing plants by micropropagation?

In tissue culture,a single germinating pollen grain will form a ........ plant.

Hardening in tissue culture is

Assertion $A$: In the plant tissue culture method,the nutrient content of the medium decreases.
Reason $R$: In this method,the biomass of cells or tissues increases.
Which option is correct for Assertion $A$ and Reason $R$?