Factors controlling adventitious bud induction and plant regeneration in mature Juniperus oxycedrus leaves cultured in vitro.

The morphogenetic capacity of mature Juniperus oxycedrus L. leaves cultured in vitro has been studied, noting nutritive, hormonal, and environmental factors inducing differentiation and development of adventitious shoots. Bud primordia formed directly from the leaves. Highest bud differentiation rates were obtained when the explants were cultured for at least 21 days on a modified Schenk and Hildebrandt solidified medium containing 0.5 μ M benzyladenine under a 16-h photoperiod. Maximum bud development and elongation was achieved on cytokinin-free medium containing 4% (wt/vol) sucrose and 0.05% (wt/vol) activated charcoal. Regenerated shoots were excised and induced to root on media with auxin. Rooting percentages up to 100% were obtained in the presence of 2.5 μ M naphthaleneacetic acid and 4% (wt/vol) sucrose. The inclusion of activated charcoal in the root induction medium drastically reduced the number of rooted shoots. Following conventional procedures, plantlets were ultimately established in soil. [ABSTRACT FROM AUTHOR]