Which of the following would result in somaclonal variation in micropropagated plants?
P. Propagation by axillary branching in the absence of plant growth regulators.
Q. Cell suspension maintained for five years before induction of somatic embryogenesis.
R. Callus induction using 20 μM 2, 4-dichlorophenoxyacetic acid followed by shoot organogenesis.
S. Shoot organogenesis from an explant in the absence of an intermediate callus phase.