There are several issues here, all of which, as the previous poster mentioned, warrant professional advice. There may be different issues depending on whether an inheritance or a lifetime transfer. The issues include :-
1) Meeting the "farmer" test
2) Agricultural Relief and Capital Gains Tax on lifetime transfers by the existing owner
3) Agricultural Relief and Capital Acquisitions Tax on the incoming farmer
4) Stamp Duty Relief for related parties
The actual existing situations, assets, liabilities of both parties would need to be examined to see what course of action is best to maximize reliefs.