IMPROVED FLAX REGENERATION FROM HYPOCOTYLS USING THIDIAZURON AS A CYTOKININ SOURCE

The effects of thidiazuron, benzyladenine and zeatin were tested with respect to bud regeneration of different flax explants from hypocotyls , cotyledons and apices of two fibre varieties (Ariane, Viking) and on e linseed variety (Antares). These three cytokinins were tested either alone or in combination with naphthalene acetic acid, indole acetic a cid or 2,4-dichlorophenoxyacetic acid. Hypocotyls were the most respon sive explants. Thidiazuron was significantly the most effective follow ed by benzyladenine, and then zeatin, in inducing organogenesis from h ypocotyl segments. The optimal thidiazuron concentration for bud regen eration from hypocotyls was 0.1-0.3 mu M in combination with 0.01 mu M of naphthalene acetic acid. Six days after plating, shoot initials be gan to appear on hypocotyl sections compared with ten to fifteen days when using benzyladenine or zeatin.