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Summary — This paper describes a method of in vitro culture establishment from shoot-tip explants taken from juvenile and mature plant material for oak (table I). The cultures established from shoot-tips were then compared with cultures derived from nodal explants for decontamination, their initial reactivity and their potential for long-term propagation. For the decontamination, the results showed that the use of shoot-tip explants is useful only when culture establishement must be made directly from source-plants growing in situ (table II). Otherwise, the use of nodal explants taken from source-plants that are maintained under active growth and controlled sanitary conditions is more advisable due to a better initial reactivity. As regards the potential for long-term propagation, the culture establishment from shoot-tips appeared truly interesting only in the case of recalcitrant clones and/or insufficient optimization of the culture methods (fig 1). However, this positive effect attenuated after a 6-7 month culture period, and the clonal effects and the management of the media became the determining factors of the culture behaviour whatever the initial explant used (fig 2).

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