In vitro plantlet regeneration from juvenile and mature Quercus robur L.

Shoot cultures of Quercus robur have been established and multiplied in vitro using original material from both juvenile seedlings and mature trees. The juvenile explants were embryos and shoot apices from 3–4-month-old seedlings. Shoot tips from the new growth of stump sprouts were used to establish initial cultures of mature trees. Of the various macronutrient formulae tried, the most satisfactory were Heller’s medium with 1 mM of (NH4)2SO4, and Gresshoff and Doy’s. A dose of 6-benzylaminopurine at 1 mg l−1 was used in initial cultures and at 0.1 mg l−1 in shoot multiplication cultures. A rooting rate of 83% was achieved with juvenile material and 63% with adult material by briefly dipping the basal ends of shoots regenerated in vitro in concentrated solutions of IBA.