(i) Electroporation: Pores are created in the host cell membrane by an electric field. Recombinant DNA is introduced into the host cell through this pore.
(ii) Micro-injection: The host cell is held by a micropipette and the recombinant DNA is injected into the host cell by a fine needle.
(iii) Biolistics: Recombinant DNA is placed on the surface of a metal particle (gold) and that particle is gunshotted into the plant cell.