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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.

A method is described to induce the differentiation of adventitious roots and buds in hypocotyl and epicotyl sections from 3-5-week-old chestnut plantlets grown in vitro. For rhizogenesis 0.1 mg l-1 of NAA or IBA was used, and BAP was necessary for bud induction. The highest rates of bud differentiation were obtained with 2 mg l-1 of BAP and 0.01 mg1-1 of NAA or IBA. Adventitious buds were multiplied in a low mineral medium with Heller’s macronutrients and 0.1 mg l-1 of BAP. The presence of IBA was necessary in the rooting stage, but no advantage was observed in reducing the sucrose level or the temperature.