FACTORS CONTROLLING ADVENTITIOUS BUD INDUCTION AND PLANT-REGENERATIONIN MATURE JUNIPERUS-OXYCEDRUS LEAVES CULTURED IN-VITRO

The morphogenetic capacity of mature Juniperus oxycedrus L. leaves cul tured in vitro has been studied, noting nutritive, hormonal, and envir onmental, factors inducing differentiation and development of adventit ious shoots. Bud primordia formed directly from the leaves. Highest bu d differentiation rates were obtained when the explants were cultured for at least 21 days on a modified Schenk and Hildebrandt solidified m edium containing 0.5 mu M benzyladenine under a 16-h photoperiod. Maxi mum bud development and elongation was achieved on cytokinin-free medi um containing 4% (wt/vol) sucrose and 0.05% (wt/vol) activated charcoa l. Regenerated shoots were excised and induced to root on media with a uxin. Rooting percentages up to 100% were obtained in the presence of 2.5 mu M naphthaleneacetic acid and 4% (wt/vol) sucrose. The inclusion of activated charcoal in the root induction medium drastically reduce d the number of rooted shoots. Following conventional procedures, plan tlets were ultimately established in soil.